Estrogen HRTs

In this section we're going to review the various estrogen preparations available commercially in the US (many of which are also available elsewhere in the world under the same or different brand names). They are grouped according to general type and route in the table below. All of these estrogen supplements require a prescription and are purchased from a pharmacy.

There is no real equivalent for estrogen or anything that contains estrogen available over the counter (we'll deal with non-hormonal approaches in another section). Use these links to go directly to a particular estrogen, or peruse the entire list to look over the range available. This is not a definitive list, even for the US. New HRTs are being licensed all the time, and as older ones fall out of patent life, the generic versions come onto the market. We can't cover all of the generics, so you may need to figure out the proprietary form they are modeled on and work from that product information.

Note: Many pharmaceutical companies and national drug databases limit access to their websites according to the country a woman is browsing from. Because of this, it can be difficult to get information from the manufacturers about HRTs not specifically sold in our home countries. Many companies have dropped publication of their prescribing information brochures or have hidden them behind restricted professional access. We have linked to other sites that publish this where we can find them, and provided several references for many HRTs because so many links are lost over time. Some of the brand names in the discussion are direct links to pdf brochure downloads so you will need a program capable of reading a pdf file to open them. Where actual prescribing information is not available, we have linked to reputable sites providing their own discussion of the HRT. The information linked to and provided here may not contain everything a woman needs to know to use any particular HRT safely and effectively; please review use instructions and characteristics with your physician and pharmacist when beginning any new HRT.

The links here are checked and updated every year or two, but they outdate rapidly and frequently. If you are having trouble opening an hrt link, try going to either drugstore.com or rxlist.com and doing a direct search there for either the brand or generic name. These sites generally publish the full FDA prescribing information accurately and fully.

So too, brands come onto the market or are withdrawn. While we try to keep up with market dynamics, we aren't always the first to know. If you've been told by a pharmacist who tried to fill a prescription for one that it's no longer available or you get a new hrt that isn't on our lists, please drop us an email to let us know.

If you are confused by the plethora of transdermal doses and wondering how one compares to another, you might find the discussion of transdermal doses elsewhere on this site helpful.

You'll see as you look through this list that we're using "human-identical" to describe HRTs with a molecular structure identical to our own estrogens, rather than "bioidentical," which has come to mean specific compounded hrts.

Oral human-identicals:

Oral synthetics:

Transbuccal human-identicals:

Transdermal human-identicals:

Transdermal synthetics:

  • none

Vaginal human-identicals:

Vaginal synthetics:

Alora is a transdermal patch that supplies human-identical estradiol. It comes in doses of 0.025, 0.05, 0.075, or 0.1 mg (per day) and is normally changed twice a week. The patch is an acrylic matrix type that can be cut to modify the dose; dose reductions are proportional to the area of patch removed. The recommended site for application is the abdomen; the butt or outer thigh can be used, but the delivered dose may be higher by about 17%-25%. Please see the Troubleshooting patches section of this site for details on using and adjusting patches. Women who give up the patch generally do so because either their skin is not capable of absorbing an even dose or because they are not able to tolerate the adhesive or having their skin continuously covered. Otherwise, the patch tends to be well thought of with a low rate of undesirable effects once the dose is balanced. (more information)

Biestrogen ("Bi-est") is a human-identical formulation containing two of the three estrogens made by the body, most typically 80-90% estriol and 10-20% estradiol although other ratios or other estrogen blends can be compounded. It is available only from a compounding pharmacy, and is available in any dose, although 1.25-2.5 mg twice a day is a usual oral starting dose range. It can be made up as a pill, a troche, a cream or a gel, and it can be combined with other hormones (although that prevents adjusting the doses of each independently). Estriol is somewhat controversial, as some practitioners feel it is safer (less carcinogenic) than estradiol and others feel that it is a metabolic waste product and carries risks just like estradiol does. Although it is a weaker estrogen, by the time its dose is increased to be as effective as an equivalent amount of estradiol, its risk profile rises as well. You may be able to lower that risk by increasing your intake of cruciferous vegetables—a good idea anyway.

Cenestin is one of the generic brands of "CES" or "synthetic conjugated estrogens." It is a plant-based (soy and yam) conjugated estrogen, heavily promoted as a non-animal alternative to Premarin. It is not exactly identical to Premarin, but it is presently accepted as a generic for it (you can read a more detailed comparison elsewhere on this website). It comes in 0.3, 0.45, 0.625, 0.9 and 1.25 mg coated time-release tablets that are not meant to be divided. Doses above 1.25 mg a day are not recommended by the manufacturer. Although it holds approval only for short-term use for vasomotor symptoms (hot flashes), that has more to do with the permitting process than overall hormone efficacy. Doctors often offer it to women who object to Premarin or who ask for a more "natural" estrogen (one of the perils of using the term "natural"). Whether or not it's what women meant to ask for, it does seem to have a slightly different effect profile—in women having HRT problems—than Premarin. It also doesn't seem to have quite as long a lifespan in the body as Premarin does, according to what women using it have told us. (more information) Jan 2017 update: We're getting reports that this hrt may no longer be on the market and that there is no particular replacement being marketed at this time.

Climara is a transdermal human-identical estradiol patch. It is supplied in doses of 0.025, 0.0375, 0.05, 0.060, 0.075 or 0.1 mg (per day) in an acrylate adhesive matrix and meant to be changed once a week. The larger the dose, the larger the patch—the delivery system is of the same "strength" per unit of area. It may be cut to modify the dose; dose reductions are proportional to the area of patch removed. The recommended site for application is the abdomen; the butt or outer thigh can be used, but the delivered dose may be higher by about 17%-25%. Please see the Troubleshooting patches section of this site for details on using and adjusting patches. Women who give up the patch generally do so because either their skin is not capable of absorbing an even dose or because they are not able to tolerate the adhesive. Otherwise, the patch tends to be well thought of with a low rate of side effects once the dose is balanced. One item of interest that used to be in the manufacturer's literature but can no longer be located on the Climara site was this comparison with another patch, Estraderm:

Both sizes of Climara maintained significantly lower peak and mean steady state estradiol levels than did the Estraderm system; however, towards the end of each treatment period, the Climara system maintained similar (day 6) or higher (day 7) serum estradiol levels than did the Estraderm system. The fluctuation index with the Climara system was 1/4 to 1/3 the fluctuation index observed with Estraderm.
This would seem to suggest that if you have a sense of levels being a problem, you might also switch around between brands of patch. The literature also notes that your serum estrogen levels decline to pre-application levels in about 12 hours. If a patch dose is too high, then, you can expect it to clear your system fairly quickly once the patch is removed. (more information)

Divigel is a 1% gel of human-identical estradiol provided in doses of 0.25, 0.5, and 1.0 mg. It is intended for once-daily dose, applied to the thighs over a specific area (5"x7"). As with other gel hrts, the potential exists for transfer to another individual and washing the area as much as an hour later can reduce the absorbed dose by 30-38%. To some extent, losses could also be expected with heavy sweating or other body-wetting activities within this time span, which may be of concern to women living in very warm climates or those who work out heavily. Because of the alcohol base, application of the gel to freshly-showered skin or in other circumstances when the pores would be open could result in stinging and irritation as well as altered uptake. The gel is supplied in single-dose packets, making it possible, if not convenient, to customize the dose used. The remaining (inactive) components of the gel are carbomer, ethanol, propylene glycol, purified water, and triethanolamine. (more information; more on this hrt elsewhere on our site; more information on troubleshooting gels)

Elestrin gel is a 0.06% gel of human-identical estradiol, in a colorless, non-staining hydroalcoholic gel base intended for once-daily dosing, applied to the upper arms. It is supplied in a non-aerosol, metered-dose pump container constructed of polypropylene. The drug product is contained within a collapsible inner liner/bag consisting of an inner and outer layer of low density polyethylene with a resealable polypropylene cap. Each pump container holds 35 g of gel and is capable of delivering 26 g of gel as 30 metered doses. Each metered dose delivers 0.87 g of gel which contains 0.52 mg of estradiol. The remaining components of the gel are ethanol, propylene glycol, diethylene glycol monoethyl ether, carbomer 940, triethanolamine, edetate disodium, and purified water. The manufacturer provides specific application instructions and precautions to do with transfer losses, especially to other people. To some extent, losses could also be expected with heavy sweating or other body-wetting activities within this time span, which may be of concern to women living in very warm climates or those who work out heavily. Because of the alcohol base, application of the gel to freshly-showered skin or in other circumstances when the pores would be open could result in stinging and irritation as well as altered uptake. Dose can be adjusted, but not conveniently. (more information; more information on troubleshooting gels)

Enjuvia is a generic formulation of synthetic conjugated estrogens (often abbreviated "CES") derived from plant sources. It is one of a number of generics in this category and closely resembles Cenestin although it is not absolutely identical to it (discussion of this in greater detail elsewhere on this site). Enjuvia is available in 0.3 mg, 0.45 mg, 0.625 mg, 0.9 mg and 1.25 mg strengths. These tablets contain the following inactive ingredients: ascorbyl palmitate, butylated hydroxyanisole, colloidal silicon dioxide, edetate disodium dehydrate, plasticized ethylcellulose, hypromellose, lactose monohydrate, magnesium stearate, purified water, iron oxide red, titanium dioxide, polyethylene glycol, polysorbate 80, triacetate and triacetin/glycerol. In addition, the 0.45 mg tablets contain iron oxide black and iron oxide yellow; the 0.9 mg tablets also contain D&C yellow no. 10 aluminum lake, FD&C blue no. 1 aluminum lake and FD&C yellow no. 6 aluminum lake; and the 1.25 mg tablets contain iron oxide yellow. For more information on using this hrt, please see the Cenestin entry. Jan 2017 update: We're getting reports that this hrt may no longer be on the market and that there is no particular replacement being marketed at this time.

Esclim is a transdermal human-identical estradiol patch. It is supplied in doses of 0.025, 0.0375, 0.05, 0.075, and 0.1 mg (per day) and is meant to be changed twice a week. It can be worn on the upper arm as well as abdomen or buttocks, and the dose delivery on the arm seems to lie about halfway between those two locations (patches on the butt deliver 17-25% higher doses than the same patch on the belly). The larger the dose, the larger the patch—the delivery system is of the same "strength" per unit of area. It is distinctive for its stretch backing, which some women feel makes it adhere better than most other patches. The manufacturer's brochure does not address whether or not it can be cut to modify the dose, but as a matrix-type patch, that may be the case. In manufacturer's testing, the dose curves of Esclim were comparable to Vivelle. Please see the Troubleshooting patches section of this site for details on using and adjusting patches. Women who give up the patch generally do so because either their skin is not capable of absorbing an even dose or because they are not able to tolerate the adhesive. Otherwise, the patch tends to be well thought of with a low rate of side effects once the dose is balanced.

Estinyl tablets contained ethinyl estradiol, a synthetic estrogen that is very strong and hence is given in much lower doses than 17-b estradiol. This brand was discontinued in 2004, but EE is still used in many birth control pills combined with various progestins. It does not seem to be available alone, without progestins, on the North American market at this time.

Estrace is human-identical estradiol in micronized form. It is available in scored uncoated pills in doses of 0.5, 1, and 2 mg and is suitable for being divided. Like most pills it can be swallowed. Because of the micronized form, it can also be taken by the transbuccal route (it dissolves in about 30 minutes, and has an inoffensive, slightly sweet flavor). It is produced from yams and soybeans. Many generics are available, but the generics contain different inert ingredients such as binders and coloring agents, so they may not perform exactly interchangeably for some uses. Generally speaking, this is a very well tolerated estrogen and a very inexpensive one (some big box stores offer it among their flat-rate prescriptions at $10/100). In our observation, most of the women who have problems with it are either not able to use the oral route well for hormones or are not well-suited to all-estradiol hrts. (FDA prescribing information )

Estrace vaginal cream is human-identical estradiol 0.01% in a nonliquefying base containing purified water, propylene glycol, stearyl alcohol, white ceresin wax, glyceryl monostearate, hydroxypropyl methylcellulose, 2208 4000 cps, sodium lauryl sulfate, methylparaben, edetate di-sodium and tertiary –butylhydroquinone (which is all pretty standard stuff). You would be hard pressed to use enough volume at this strength to provide systemic coverage, but it is an effective, if a bit messy, way to add supplementary estrogen to the genitourinary tissues. (more information on this product; more information on vaginal estrogen use on our website)

Estraderm is a transdermal human-identical estradiol patch. It is supplied in doses of 0.05, and 0.1 mg (per day) and is meant to be changed twice a week. The estradiol is derived from sweet potato. The patch cannot be cut to modify the dose since hormone delivery is controlled by the patch membrane, not the adhesive matrix. One item of interest that used to be available in the manufacturer's literature for Climara was this comparison with Estraderm:
Both sizes of Climara maintained significantly lower peak and mean steady state estradiol levels than did the Estraderm system; however, towards the end of each treatment period, the Climara system maintained similar (day 6) or higher (day 7) serum estradiol levels than did the Estraderm system. The fluctuation index with the Climara system was 1/4 to 1/3 the fluctuation index observed with Estraderm.
This would seem to suggest that if you have a sense of levels being a problem, you might also switch around between brands of patch. The recommended site for application is the abdomen; the butt or outer thigh can be used, but the delivered dose may be higher by about 17%-25%. Patches should be rotated to different locations with at least a week's rest between uses of a specific location. Please see the Troubleshooting patches section of this site for details on using and adjusting patches. Women who give up the patch generally do so because either their skin is not capable of absorbing an even dose or because they are not able to tolerate the adhesive. Otherwise, the patch tends to be well thought of once the dose is balanced. (more information)

Estrasorb is a human-identical estradiol (estradiol hemihydrate) in a lotion base composed of soybean oil, water, polysorbate 80, and ethanol. Estrasorb is packaged in foil pouches and the daily recommended dose of two pouches delivers 0.05 mg of estradiol*. According to the directions, each pouch is spread over an entire leg: thigh, calf and buttocks, and then must be allowed to absorb until the skin is dry to avoid loss to clothing. Interestingly, the prescribing information goes on to note:
Estradiol was detected on the skin at 2 and 8 hours post-application. Washing the application area with soap and water 8 hours post-application removed detectable estradiol from the application site. Upon physical contact of Estrasorb application sites by adult males at 2 and 8 hours post-application over a two-day period in a second study, a mean increase of approximately 25% in serum estradiol concentration was identified.
This is fairly significant, and we have no idea—because we haven't found corresponding information for other topical HRTs—whether this represents poor absorption of this particular product or is common to all topical preparations. User experience reports have been that the lotion is readily and rapidly absorbed, as one would expect with application over such a large area, and for women sensitive to hormone fluctuations, this rapid uptake can cause unpleasant symptoms like headaches. Doctors are offering it to patients when they have problems with other hrts, and it provides a retail alternative within the transdermal realm for doctors who are not comfortable prescribing compounded hrts. While measuring out doses of the lotion is not likely to be convenient, it is at least possible to customize the dose of this product. (more information) Although the original manufacturer, Novavax, discontinued producing this hrt in Oct. 2007, it has since been sold to Graceway Pharmaceuticals and remains in production and available.

*This dose is confusing if you try to work the numbers from the package. The packets clearly state that they contain 1.74g with 2.5mg per gram of cream. That looks as though your intake should figure up to be 8.7mg of estradiol per dose. Nonetheless, the package insert, approved by the US FDA states:
Estrasorb (estradiol topical emulsion) is designed to deliver estradiol to the blood circulation following topical application of an emulsion. Each gram of Estrasorb contains 2.5 mg of estradiol hemihydrate USP, EP, which is encapsulated using a micellar nanoparticle technology. Estrasorb is packaged in foil pouches containing 1.74 grams of drug product. Daily topical application of the contents of two foil pouches provides systemic delivery of 0.05 mg of estradiol per day. [emphasis added--ed.]
As ever, it's important to be very careful not to confuse apples with oranges in doing this math. You can read more about transdermal delivery amounts elsewhere on our site.

Estratab contained esterified estrogens, a compound that is 75-85% estrone. It has been unavailable since spring 2001 although still listed on some websites. Some sources report various rumors of its return at various doses, the time since it was discontinued argues against this. Menest was offered by many pharmacists as being the same thing, although we've read plenty of comments from women who were switched to the effect that it didn't work quite the same way as estratab did for them. If we can confirm in the future that it's back on the market, we'll post it here.

Estring is an estrogen-releasing silicone ring meant to be worn in the upper vagina (even by women who have had their cervix removed) to provide low-dose human-identical estradiol to genitourinary tissues without significantly affecting systemic estrogen levels. It contains a total of 2 mg and releases at approximately 7.5 micrograms per day over 3 months. The outer diameter is 55 mm, cross section 9 mm, and core diameter 2 mm. Its efficacy is comparable to vaginal estrogen creams, but of course is much less messy and requires less fiddling with. If it falls out, it can be rinsed and reinserted; it should not be used, the manufacturer says, during an active vaginal infection. It can be left in during intercourse, so presumably (it's not addressed in the info leaflet) it does not provide significant estrogen exposure to your partner; it can, of course, be removed and reinserted if you prefer. It's very important to distinguish between Estring, which is meant for local effect only, from Femring, which is a systemic HRT that also comes in vaginal ring form. (more information)

EstroGel is a topical formulation of 0.06% human-identical estradiol (a dose of 1.25 gm contains 0.75 mg of estradiol) in a clear colorless gel made up of purified water, alcohol, triethanolamine and carbomer 934P. The only dose licensed is the 1.25 gm one, which is dispensed from a sealed metered pump bottle that is rated for 64 doses. Dose customization is possible but would require removing and measuring the dose with something else as partial pumps would be of questionable accuracy. We have seen several user complaints that the pump is not fully accurate in the amount it dispenses, to the extent that it proves to be a source of instability. It is meant to be applied to the entire arm, from wrist to shoulder. The prescribing information states that it "dries in 2 to 5 minutes" but isn't clear whether this means it's fully absorbed in this time or whether the vehicle is dry but estrogen sits on the skin thereafter until it is gradually absorbed. No information is recorded with respect to passive transfer to others, although the prescribing information does note that "site washing one hour after the application resulted in a 22% mean decrease in average 24-hour serum concentrations of estradiol" so it would be prudent to consider transfer possible. To some extent, losses could also be expected with heavy sweating or other body-wetting activities within this time span, which may be of concern to women living in very warm climates or those who work out heavily. Because of the alcohol base, application of the gel to freshly-showered skin or in other circumstances when the pores would be open could result in stinging and irritation as well as altered uptake. It's also important to understand, especially when converting doses to gel hrts, why the dose delivered by the hrt is not necessarily the dose that makes its way to systemic circulation. This is covered in more depth elsewhere on this site. (more information)

Evamist is a transdermal spray delivery of human-identical estradiol. One spray delivers 90 mcL which contains 1.53 mg estradiol; starting dose is one spray daily to the forearm but the dose may "increase to two or three sprays daily to forearm based upon clinical response" to adjacent, non-overlapping areas. As with gel hrts, the dose remains on the skin surface as the dispensing reservoir, meaning that it can be transferred to others and its uptake impaired by the use of sun screen or, presumably, other oily toiletries. It's a lossy delivery, with the delivered dose per spray nominally only 0.21 mg, although removal of the application bell before the dose has fully settled onto the skin could result in additional hrt being inhaled—which is not a tested or recommended practice. (more information)

FemPatch is another human-identical estradiol matrix patch meant to be changed weekly and is often cited as a generic equivalent to Climara. Doses are variously reported as 0.025, 0.05 and 0.1 mg (per day) but sources are not uniform and we weren't successful in finding the prescribing information online; the smallest dose seems to have the most references to it. There are references to it having been approved in the late 90s and a few mentions of it having then been discontinued, but we have no definitive information. Lacking any further detail, we can only guess that the information listed here under the Climara section would be roughly applicable. If anyone has the prescribing information that they can pass along a link to or a scan of, we'd be happy to make it available.

Femring is an estrogen-releasing silicone ring worn in the upper vagina and available in two strengths. The 0.05 mg/day dose version has a central core that contains 12.4 mg of estradiol acetate, and the 0.10 mg/day contains 24.8 mg; both release the specified level of hormone for 3 months. Unlike Estring, Femring is meant to provide systemic HRT. Although it is not strictly human-identical as released from the ring, it is readily and rapidly converted to human-identical estradiol in circulation. Because this conversion is necessary to allow it to pass through vaginal tissues before being activated, it does not overwhelm local tissues with excessively high estrogen exposure. Any vaginal effects it has, then, come back through general circulation, not local tissue distribution: this is not a treatment for vaginal atrophy.

The prescribing information goes on to note that
drug delivery from Femring is rapid for the first hour and then declines to a relatively constant rate for the remainder of the 3-month dosing interval. In vitro studies have shown that this initial release is higher as the rings age upon storage.
The ring, which fits around the cervix (or vaginal cuff) and remains in place for the three months dosing life, may be left in place during treatment for any vaginal infections according to the prescribing information. The literature does not directly address safety of a sexual partner, but says that it may be left in place during intercourse or removed and replaced according to the desire of the user. Additional ingredients include: cured silicone elastomer composed of dimethyl polysiloxane silanol, silica (diatomaceous earth), normal propyl orthosilicate, stannous octoate, and barium sulfate. There are no coloring agents in Femring. User complaints that seem to result in women giving this hrt up include inadequate lifespan (they draw it down too rapidly) and abdominal cramping or complaints of fullness. (more information)

Femtrace is an oral pill of estradiol acetate plus inert ingredients ferric oxide, povidone, lactose monohydrate, microcrystalline cellulose, croscarmellose sodium, silicon dioxide, magnesium stearate and acetic acid; ferric oxide, a coloring agent, is not an ingredient in the 0.9 mg tablets. It comes in doses of 0.45, 0.9 or 1.8 mg and we could not locate information on how divisible it is although photos suggest that it is an uncoated tablet that could be easily cut. The acetate form of the hormone is readily converted to human-identical estradiol once absorbed into the system. We don't have any information as to whether this pill is suitable for transbuccal use.

Gynodiol is considered a generic of Estrace human-identical oral estradiol, and is available from several different manufacturers in divisible tablets in doses of 0.5, 1.0, 1.5, or 2.0 mg (photos). We were not able to locate a prescribing information sheet specific to this brand, but the general characteristics of Estrace would be assumed to apply. Women who have used a number of the different brands of this generic category report that they may not be entirely identical but are interchangeable with some minor dose adjustments. It can be used for transbuccal delivery.

Menest contains esterified estrogens, a compound that is 75-85% estrone but not entirely human-identical:
Esterified estrogens is a mixture of the sodium salts of the sulfate esters of the estrogenic substances, principally estrone, that are of the type excreted by pregnant mares. It contains the concomitant component, 17α-estradiol. The content of total esterified estrogens is not less than 90 percent and not more than 110 percent of the labeled amount. Esterified estrogens contain not less than 75 percent and not more than 85 percent of sodium estrone sulfate, and not less than 6 percent and not more than 15 percent of sodium equilin sulfate, in such proportion that the total of these two components is not less than 90 percent, all percentages being calculated on the basis of the total esterified estrogens content.
It comes in 0.3, 0.625, 1.25, and 2.5 mg tablets that are not scored for dividing. It is synthesized from soy. Estrone is the weaker of the two major estrogens made by the body, and the one typically found at highest levels in naturally-menopaused women. Some women find it appealing that they are achieving a state somewhat comparable to natural menopause, while others who do well with it are women who find all-estradiol HRT to provide an excess of estrogenic activity. Because it is less potent than estradiol, some doctors consider it to have a lower risk of stimulating cancer, especially of the endometrium; others feel that the fact that it is normally and freely converted to estradiol by the body negates any such protection. (more information, photos)

Menostar is an acrylate matrix patch meant to be changed weekly that delivers human-identical estradiol in a single dose of 0.014 mg (per day). At this low dose, it is licensed only for osteoporosis prevention, not even menopausal hot flashes. Its performance, aside from dose strength, is comparable to that of Climara. (more information)

Minivelle is a transdermal patch that supplies human-identical estradiol. It's being marketed as equivalent to (or possibly a generic for) the Vivelle Dot and uses the same adhesive ingredients, so it should perform generally in the same manner for a new user although a user switching from the V-Dot may notice a week or two of transitional symptoms. Like the V-Dot, it can be cut to adjust dose. It differs from V-Dot in that it is smaller in physical area, something that can be either a benefit (if a woman is having problems finding unwrinkled realestate for application) or a drawback (if she's cutting the patch down to adjust the dose) depending upon circumstances. Early user reports indicate that sticking to clothing may be a problem, so this patch in particular should be powdered after application. Please see the discussion of the V-Dot here for more on patch use and the discussion of this patch on our forums for more details on switching between the two brands.

Ogen is piperazine estrone sulfate (formerly known as estropipate) synthesized from vegetable sources—probably soy or yam. It comes in 0.625, 1.25, and 2.5 mg scored tablets that are meant to be dividable for dose customization. While many references to it remain available online, as of 2014 pharmacists trying to order it have reported that it is no longer manufactured. We'll update this listing when/if we obtain solid information either way.

Ogen cream is estrone, solubilized as the sulfate and stabilized with piperazine in a cream containing glycerin, mineral oil, glyceryl monostearate, polyethylene glycol ether complex of higher fatty alcohols, cetyl alcohol, anhydrous lanolin, sodium biphosphate, cis-N-(3-chloroallyl) hexaminium chloride, propylparaben, methylparaben, piperazine hexahydrate, citric acid and water containing 1.5 mg/gm. It is licensed for the treatment of vaginal and vulvar atrophy. We do not have reliable information as to whether this is still on the market, but given the discontinuation of Ogen (see above), we expect that it is not.

Ortho-Est is piperazine estrone sulfate (formerly known as estropipate) synthesized from vegetable sources—probably soy or yam. It comes in 0.625, and 1.25 mg scored tablets that are meant to be dividable for dose customization. While many references to it remain available online, as of 2014 pharmacists trying to order it have reported that it is no longer manufactured. We'll update this listing when/if we obtain solid information either way.

Premarin is the great-grandmother of prescription estrogens and once was the most widely-prescribed drug in the US. It comes as a non-dividable coated pill in 0.3, 0.625, 0.9, 1.25 and 2.5 mg dose strengths. The active ingredient is listed as conjugated equine estrogens. It is derived from the urine of pregnant mares (hence the name), leading to ethical objections to its use by some women. It contains a large number of hormonal compounds that are capable of acting in some ways like estrogen and progesterone and some compounds that are testosterone-related but not testosterone. There used to be a listing that compared what's in Premarin with what Cenestin, a plant-based comparable, contained at the Cenestin website, but it has since been removed. We've transcribed it and posted the list as well as a discussion of the differences and similarities between several such hrts for you elsewhere on this site. The FDA has asked the manufacturer for a full identification of everything that's in Premarin—which the manufacturer admitted they haven't quite worked out yet.

Because the hormonal agents it contains are not human-identical, it doesn't work the same way or break down the same way as our own estrogens. This can be good or bad, depending upon your needs. One thing peculiar to Premarin that may be relevant as you tune this HRT to your needs or change from it to another form of HRT is that Premarin stays in the body for a considerable period of time after you take it, and the longer you take it, the longer it takes to wear off. For someone who has taken it for only weeks, this clearance is weeks as well; if you've taken it for years, it may take months to fully leave your system. This means that as you switch, you'll have to gradually increase your new HRT as the Premarin wanes—and you may or may not have hot flashes from that dose fluctuation the whole time.

While Premarin has the highest rate of negative effects in women we've heard from who are having problems with their HRT, we can obviously tell from the sales figures that a lot of other women must be taking it and doing just fine on it. Conjugated estrogens taken orally have been linked to a higher incidence of hypertension, although studies provide conflicting data on this. We've seen it observed by other health professionals that women taking Premarin are often taking a number of other drugs for "other" problems like asthma, depression, allergies, etc. (that all have hormonal links), but it's hard to guess whether that might have to do with the hormone form or the doctor's style. Many doctors will only prescribe Premarin for HRT because it's the one all the studies have been done on and thus it's the one most "proven." However, you have to keep in mind that these studies were paid for by Premarin's manufacturer, who have been aggressively pursuing the market since the Women's Health Initiative study led to such market losses for their product. As part of their marketing efforts, Wyeth is presently seeking to have compounding of HRTs significantly restricted by the FDA. (more information)

Premarin vaginal cream contains 0.625 mg conjugated estrogens (per gram of cream) in a nonliquefying base containing cetyl esters wax, cetyl alcohol, white wax, glyceryl monostearate, propylene glycol monostearate, methyl stearate, benzyl alcohol, sodium lauryl sulfate, glycerin, and mineral oil. It carries the same profile as oral Premarin but at this dose is unlikely to have systemic effect. It is intended for local treatment of genitourinary tissues. As a class, vaginal creams tend to be messier delivery systems than the newer pills or rings designed for the same purpose, but can be given as a more intensive treatment rather than being restricted to low maintenance doses. (more information)

Triestrogen ("Tri-est") is a human-identical combination of the three estrogens normally produced by the body. The usual proportion is 10% estrone, 10% estradiol, and 80% estriol (based on mg of content, not relative potency), but it can be compounded to any ratio--the name simply references that it contains these three estrogens and does not specify the amounts of each used in the blend nor the overall daily dose. It is available only from a compounding pharmacy and can be made up in any dose although 1.25 –2.5 mg twice a day is the usual oral dose. It can be made up as capsule, cream, or troche. This combination was developed by Dr. Jonathan Wright as a means of reducing the exposure to strong estradiol while still providing enough total estrogen to alleviate symptoms. Critics contend that by the time you take enough to be effective, you have taken enough to put yourself back in the risk category. Both sources suggest that you can modify this risk by increasing your intake of cruciferous vegetables.

Vagifem is a low-dose human-identical estradiol pill meant to be inserted into the vagina to apply estrogen directly to genitourinary tissues without affecting systemic hormone levels. It comes in two doses, containing 10 micrograms of estradiol, and comes in boxes of 15 with a thin applicator that is reportedly very easy to use. Comments are very favorable on its efficacy in dealing with lingering vaginal dryness in women who feel they are otherwise well-balanced on their systemic HRT, but as with any new/specialty drug, it tends to be rather expensive. Directions call for using one dose daily for two weeks and then cutting back to two doses a week, but you can expect to modify this based on your doctor's (and your, we hope) assessment of your needs. Because it is a fixed maintenance dose, when used to treat existing severe symptoms initial progress may be rather slow.

Vivelle is a transdermal human-identical estradiol patch. It is supplied in doses of 0.025, 0.0375, 0.05, 0.075, and 0.1 mg (per day) and is changed twice a week. This is not the same thing as the Vivelle Dot and they are not interchangeable so it's important to check your prescription every time it's filled to be sure you have actually been given what you expect. The larger the dose, the larger the patch—the delivery system is of the same "strength" per unit of area. It may be cut to modify the dose; dose reductions are proportional to the area of patch removed. The recommended site for application is the abdomen; the butt or outer thigh can be used, but the delivered dose may be higher by about 17%-25%. Circulating estrogen levels return to pre-application baselines within 24 hours of removing the patch. The manufacturer recommends stopping an oral hormone 1 week before switching to the patch, but okays beginning sooner "if menopausal symptoms reappear." Please see the Troubleshooting patches section of this site for details on using and adjusting patches. Women who give up the patch generally do so because either their skin is not capable of absorbing an even dose or because they are not able to tolerate the adhesive. Otherwise, the patch tends to be well thought of with a low rate of undesirable effects once the dose is balanced. (more information)

Vivelle Dot is a transdermal human-identical estradiol patch. It is supplied in doses of 0.025, 0.0375, 0.05, 0.075, and 0.1 mg (per day) and is changed twice a week. The larger the dose, the larger the patch—the delivery system is of the same "strength" per unit of area. It may be cut to modify the dose; dose reductions are proportional to the area of patch removed. This is not the same thing as the Vivelle and they are not interchangeable so it's important to check your prescription every time it's filled to be sure you have what you expect. This patch is about 1/3 the size of the regular Vivelle (about the size of a postage stamp) and is noted for its tenacious adhesive, which is actually quite different in composition from most of the other patches. Women who have had adhesion failures with other patches may find that this one sticks just fine and women with particularly fragile skin may actually have difficulty removing it (soften the adhesive with a warm hair dryer first, is advice offered by users of the dot). The recommended site for application is the abdomen; the butt or outer thigh can be used, but the delivered dose may be higher by about 17%-25%. Circulating estrogen levels return to pre-application baselines within 24 hours of removing the patch. The manufacturer recommends stopping an oral hormone 1 week before switching to the patch, but okays beginning sooner "if menopausal symptoms reappear." Please see the Troubleshooting patches section of this site for details on using and adjusting patches. Women who give up the patch generally do so because either their skin is not capable of absorbing an even dose or because they are not able to tolerate the adhesive. Otherwise, the patch tends to be well thought of with a low rate of side effects once the dose is balanced. (more information)