Testosterone for women in general practice: who to treat, what to measure, how to dose and monitor, and what it does not do

Main expert (answering the questions)

Professor Susan Davis, introduced as a clinician researcher and internationally recognised expert in sex hormones across the female lifespan and menopause; leads the Monash Women's Health Research Program, heads the Women's Endocrine Clinic at Alfred Health, Melbourne, and is an Executive Council member of the Australian Academy of Health and Medical Sciences. In the transcript she is addressed as "Susan" and thanks "Sally" before answering, so the clinical content on this page is hers unless stated.

Co-presenter (asking the questions)

Dr Sally Sweeney, specialist GP and clinician researcher with over 20 years in sexual and reproductive health care; works in private general practice and a specialist multidisciplinary women's clinic, and previously spent 15 years as a senior clinician with Family Planning Australia (as transcribed). Sally steered the session and added practical GP points, for example about the formulation, the Australasian Menopause Society (AMS) fact sheets and checking how a patient is applying the cream.

Session context

Otter title Testosterone Therapy for Women · id 0PX4dCfGz7n1xl6zAdOhGkeoAe8 · ~25 min. Introduced by an unnamed chair. Otter split the audio across eight speaker labels; a few of Sally's comments are merged into Susan's turns in the export, and we have attributed those by context.

Key messages for GPs

• One evidence-based reason to prescribe: a postmenopausal woman with low sexual desire that bothers her (hypoactive sexual desire disorder, HSDD). Susan keeps a "pretty low threshold" for a trial.
• You are not looking for low testosterone. Blood levels bear no relationship to sexual desire in postmenopausal women. Baseline tests exist to find the woman whose level is unexpectedly high, or whose SHBG is out of range.
• Measure total testosterone and SHBG at baseline. A standard immunoassay is fine. Do not use the free androgen index or calculated free testosterone.
• Use the approved female formulation (a 1% cream with a measuring syringe), not compounded products or fractions of male products.
• Check a level at about three weeks to catch accidental overdosing. Benefit takes several weeks to appear; allow three to six months to judge it.
• Keep total testosterone within the premenopausal range, accepting up to about 1.5 times the upper limit of the premenopausal reference range. Treat the patient, not the number.
• No benefit for mood, cognition, energy, bone or muscle on current trial evidence. It is "not the silver bullet".
• She does not need to be on oestrogen, and it works as well in women on SSRIs or SNRIs.

Who is it for: low desire that bothers her

Susan: the only reason to prescribe testosterone today is a postmenopausal woman who presents with low sexual desire that bothers her. HSDD is a very medicalised label ("patients don't come in and say, I've got HSDD"), so listen for the description instead. She uses the ICD-11 definition, which she called the best and most accepted:

• lack of sexual thoughts and fantasies;
• lack of interest in sex;
• lack of responsive desire (when a partner initiates intimacy she does not feel interested in responding);
• present for at least several months (it does not have to be six).

Testosterone across the lifespan

From about age 20, women's blood testosterone falls steadily with age, with no change at natural menopause. The decline continues slowly until about 60, after which several studies show levels rise slightly. Susan thinks this subtle rise may explain why some women notice more facial hair in their 70s.

Baseline tests: total testosterone and SHBG

Women often arrive "obsessing" over their testosterone level, and GPs face a menu of free, total and bioavailable testosterone plus SHBG. Susan's answer was simple.

• You are not diagnosing low testosterone. Her group had just published in Fertility and Sterility that blood testosterone levels bear no relationship to sexual desire in postmenopausal women.
• Why test at all? To exclude the woman with an unexpectedly high testosterone (be more cautious about treating), and to spot an SHBG that is out of range, high or low, because it changes how you read levels on treatment.
• An immunoassay is enough. You do not need mass spectrometry or great precision for this purpose. Sally added that not all labs offer mass spectrometry anyway.
• Order: total testosterone and SHBG.

Prescribing and applying the cream

Australia is one of only a few countries with an approved female testosterone formulation, and there is only one. It is a 1% cream: the patient receives a tube of white cream and a small orange measuring syringe. Sally mentioned a metered-dose pump pack is expected later in the year. (The brand name was garbled in the transcript, so it is not named here.)

• Warn the patient what she will get (a tube and a syringe). Occasionally pharmacies still offer "something less expensive" that turns out to be compounded, which is not what was prescribed.
• Dose as described: put the syringe into the tube and draw up half a millilitre (transcribed "half mill"). Tell her the measuring is not highly accurate and not to get anxious about it. Many women end up judging it on a fingertip, and Susan is "pretty well okay" with that.
• Why the female product matters: at 1% you have to apply quite a lot extra to reach high levels. Male products are much more concentrated, and it is very hard for a woman to measure a tiny fraction of one accurately without overdosing. Sally flagged social media advice to use one-tenth doses of male products, and compounded products, as things to steer patients away from.
• Resources: the AMS has a fact sheet on why a female-specific formulation is safer, and a newer testosterone fact sheet, both free on the AMS website.

Monitoring: clinical and biochemical

• When to test: product information suggests a level three to six weeks after starting. Susan explained the six weeks comes from UK rules; in Australia she prefers about three weeks.
• Why so early: to pick up a woman who is inadvertently over-applying before she develops acne or extra hair growth. Tell her she is unlikely to notice any benefit by then.
• When to expect benefit: she should use it for a good four to six weeks before noticing anything; Sally added that it can take three to six months to see the full effect.
• Target: keep total testosterone in the premenopausal range. The lab will usually print a reference range for her age (for a 52-year-old, a postmenopausal range), so you may have to look up the premenopausal range yourself. Susan readily accepts up to about 1.5 times the upper limit of the premenopausal reference range.
• Slightly over is fine: if the ceiling works out at, say, 2.5 nmol/L and she is at 2.8 with no side effects, "don't get mixed up" about it; assays are not perfect. (These example numbers were partly garbled; see caveats.)
• Clinical review is the real safety check. Susan has seen plenty of women develop scalp hair thinning even with levels in the normal range. Ask about acne, increased body or facial hair and scalp hair.
• An unexpectedly high level? Sally: confirm exactly how she is using it. Some women adopt a "more is better" mindset; a colleague's patient was applying it vaginally, which pushed her levels up.

Breast and cardiovascular safety

• Randomised trial data extend to about two years. There are no randomised data beyond that, though longer follow-up data (as we read the garbled "within a 20 year follow up") showed no signal of concern.
• Breast: no signal for increased breast cancer risk. There is also no randomised evidence that testosterone prevents breast cancer, so do not promise that.
• Cardiovascular: in women without active cardiovascular disease it "appears to be extremely safe". Used transdermally, it does not raise blood pressure or lipids.
• No safety data for excessive doses. Some women use very high doses; we cannot reassure them.

What testosterone does not do

Sally raised the social media message, often from American doctor influencers, that testosterone is "the third pillar" of hormone therapy, along with small observational signals for mood, cognition and bone. Susan's view of the trial evidence:

• Mood: no improvement in clinical trials. One very good study in women with major depression found the placebo response equal to the testosterone response.
• Self-reported outcomes (mood, cognition, wellbeing, energy) show huge placebo effects, which does not mean the treatment works.
• Bone: no sound evidence; her group will report a study later this year.
• Muscle: the only positive studies used doses giving almost male blood levels. More data are coming, "so there might be something there", but not yet.

Premenopausal and perimenopausal women

• Levels fall well before menopause, and many younger women ask about testosterone for low libido. But not a single study has yet looked at testosterone in perimenopausal women. Susan's team is running a randomised trial in peri- and premenopausal women.
• Sexual dysfunction does increase in the early perimenopause, but whether testosterone helps is unknown.
• In premenopausal Australian women, low desire with distress affects only about 9 to 10%, far less than in peri- and postmenopausal women. In this group look hard for other causes: relationship issues, depressive symptoms and other psychosocial factors.

Rapid-fire questions

High SHBG at baseline

A common cause is oral oestrogen (transcribed "bone estrogen"). SHBG has roles beyond transport: high SHBG is associated with a lower risk of metabolic syndrome, and low SHBG strongly predicts type 2 diabetes and metabolic syndrome in women. For testosterone prescribing it is simply a guide to reading levels.

• Women with very high SHBG tend to get less benefit at a given dose. It is a tendency, not a reason not to treat.
• If she is on oral oestrogen, switch to transdermal estradiol before starting testosterone.
• Do not calculate a free androgen index (unreliable) or free testosterone (labs use three different equations that give different answers).
• With ultra-low SHBG, if she is benefiting and her level stays low, that is fine. "Treat patients, not blood levels."

How long can she stay on it?

If she is happy, well, and her levels and symptoms are fine, Susan would leave her on it for as long as she wants it.

Does she need to be on oestrogen?

No. Large studies in postmenopausal women not on oestrogen have shown testosterone to be effective and safe.

Breast cancer survivors

• Susan is very cautious.
• On tamoxifen: she has consistently found no benefit, possibly because tamoxifen blocks oestrogen receptors throughout the body.
• On aromatase inhibitors: very cautious; there are no safety data. These women's testosterone levels may already rise because conversion to oestrogen is blocked. A multicentre Australian study of testosterone in women on aromatase inhibitors is due to start.
• Do not start testosterone without consulting her oncologist or surgeon. (The transcript literally says "I certainly would initiate", which in context is almost certainly "would not"; see caveats.) Sally: as a GP, assemble a multidisciplinary team around the decision.

After hysterectomy or oophorectomy

• Women who have had a hysterectomy tend to have slightly lower testosterone; women with bilateral oophorectomy at any age tend to have lower levels, though the gap narrows with age.
• The reason to prescribe is unchanged: clinical need, not blood levels. Plenty of women after bilateral oophorectomy on oestrogen have normal sexual function. "We're not adding something without a reason."
• For complex situations (a gynaecological malignancy, lupus or another condition that could affect the decision), agree the plan with the other doctors involved, so the patient is not "the meat in the sandwich" of differing specialist opinions.

On an SSRI or SNRI with sexual dysfunction

Yes, it can be added. Testosterone is equally beneficial for sexual dysfunction in women on SSRIs and SNRIs.

GP clinic checklist

1. Confirm the indication: postmenopausal, low desire (ICD-11 features) for several months, and it bothers her. Explore relationship, mood and other factors.
2. Baseline total testosterone and SHBG (immunoassay). Look for an unexpectedly high level or out-of-range SHBG, not a low level.
3. On oral oestrogen with high SHBG: consider switching to transdermal estradiol first.
4. Prescribe the approved female 1% cream; explain the tube and syringe, the dose and that small measuring errors are fine. No compounded or male products.
5. Level at about three weeks; keep total testosterone up to about 1.5 times the premenopausal upper limit.
6. Review clinically: acne, hirsutism, scalp hair thinning, and how she applies it.
7. Judge benefit over three to six months; continue if helping and well.
8. Breast cancer history or complex illness: decide with the treating specialists.

Transcript caveats

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