Does PT-141 Increase Sexual Desire in Women, or Mainly Physical Arousal? What the Trials Measured

What did the PT-141 approval trials actually measure?

Desire, plus distress about desire. Neither one is physical.

Bremelanotide was approved as Vyleesi on June 21, 2019 on the strength of two identical Phase 3 trials, RECONNECT, running 24 weeks in 1,267 randomized women.¹⁴ Both had the same pair of co-primary endpoints, and the FDA label names them.

The first was "Change from baseline to end of study (EOS) in the Desire domain from the Female Sexual Function Index (FSFI)," a two-question self-report where "The FSFI Desire Domain score ranged from 1.2 to 6."¹

The second was a single distress question, item 13 of the Female Sexual Distress Scale, Desire/Arousal/Orgasm version, which asks how often a woman felt "Bothered by low sexual desire?" answered on a scale of 0 for never to 4 for always, over a 30-day recall.¹

So the regulator approved the drug on a desire question and a distress-about-desire question. Both are things a woman reports. Neither is a thing an instrument records.

Arousal was in there, as a secondary endpoint, and it is also a questionnaire. Four self-report questions make up that domain, all of them about feeling "turned on" during sexual activity.⁵ The 2021 re-analysis records it as a secondary outcome reported as a categorical result rather than as a score.² Either way it is not a measurement of the body, and no published RECONNECT endpoint measured lubrication by instrument, genital blood flow, or any other physiological signal.

How much did PT-141 improve desire?

About a third of a point, on a scale with 4.8 usable points.

The published paper reports the between-group difference: desire rose by 0.30 in one study and 0.42 in the other, with an integrated figure of 0.35, all at p < .001.⁴ Distress fell by 0.37 and 0.29, integrated at 0.33.⁴

	Study 1	Study 2
Desire, bremelanotide mean change	0.5	0.6
Desire, placebo mean change	0.2	0.2
Desire, median change on drug	0.6	0.6
Desire, median change on placebo	0	0
p-value	0.0002	< 0.0001

From the FDA label, read at source. These are within-arm changes, not the drug effect. Subtracting one from the other gives the drug effect. The paper puts it at 0.30 and 0.42.¹⁴

That distinction catches people out constantly. A 0.6 median change on the drug is not a 0.6 benefit, because placebo moved too. Consumer coverage frequently quotes the larger number.

For scale, the label's exploratory responder analysis counted "at least 1.2-point increase from baseline in FSFI-Desire Domain score."¹ That is an individual threshold and 0.35 is a group average, so one is not a fraction of the other. On the responder framing, a 2020 commentary reports a response rate of "58% vs 35% for drug vs placebo."⁶

A re-analysis published in The Journal of Sex Research in 2021 recomputed the effect from the FDA's own data and put the desire difference at .36 units, close to the paper's figure, concluding that "bremelanotide offers little benefit for women diagnosed with HSDD."² A separate commentary in 2020 called the benefits "only small" in the average patient.⁶

Did any PT-141 trial measure physical arousal?

Once, in 2006, by machine. It did not move.

A crossover pilot published in The Journal of Sexual Medicine gave 18 premenopausal women a single 20 mg intranasal dose of bremelanotide or placebo and measured vaginal pulse amplitude with vaginal photoplethysmography while they watched neutral and erotic videos.³ That change in pulse amplitude was one of the study's two main outcome measures, alongside the women's own perceptions. No other trial in the bremelanotide record was built around a physical measurement at all.

The result, in the authors' full sentence: "Vaginal vasocongestion did not change significantly while viewing erotic videos following bremelanotide administration compared with placebo."³ The erotic videos did produce a response. Maximum amplitude change, meaning peak pulse amplitude during the erotic video against the neutral one, came to 9.6% on the drug and 14.9% on placebo, p = 0.27.³ What did not differ was drug against placebo.

Read the direction of those numbers. Genital blood flow was numerically lower on bremelanotide, not higher. Statistical significance is absent, so nobody should read it as the drug reducing anything. What it cannot support is the claim that the drug increases physical arousal.

Those same women reported more desire. Sixty-seven percent said they experienced sexual desire after bremelanotide against 22% after placebo, p = 0.0114.³ Reported feelings of genital arousal rose too, from 39% to 72%, but that comparison did not reach significance at p = 0.0833.³ Among the women who had sex within 24 hours, significantly more were satisfied with their level of arousal after bremelanotide than after placebo, p = 0.0256.³

Four limits belong on this study and the page will not hide them. Eighteen women is a pilot. The dose and route, 20 mg intranasal, are not the approved product. Vyleesi is 1.75 mg by injection. Participants had female sexual arousal disorder, not HSDD, so these are not the women the drug was later approved for. Three of the six authors were employees of the company developing the compound.³

Did PT-141 change what actually happened?

No. The count of satisfying sexual events did not move.

Beyond questionnaires, RECONNECT counted satisfying sexual events, logged by participants. The FDA label states: "There was no significant difference between treatment groups in the change from baseline to end of study visit" in that count.¹ Study 1 returned p = 0.76 and Study 2 p = 0.70.¹

The 2021 re-analysis puts it more bluntly: "In terms of number of satisfying sexual events, bremelanotide provides no benefit."²

One behavioral number did move, and it was not prespecified. The percentage of sexual encounters rated satisfying rose by 25.0% on the drug against 9.8% on placebo, p < .001.² That figure deserves its caveat rather than burial: the same re-analysis records it as not prespecified in the trial registration and says of those diary-derived outcomes that "it seems these outcomes were concocted post-hoc."² A proportion that was not planned in advance, reported alongside a planned count that did not move, is a weaker thing than a planned result. It is not nothing.

So across 1,267 women and 24 weeks, a desire score moved, a distress score moved, and the number of satisfying sexual encounters did not.

Two readings of that are both defensible and the page will not pretend otherwise. One holds that HSDD is a disorder of desire and distress, so improving those is the point and event counts were never the target. The other holds that a drug whose planned behavioral endpoint did not move has produced a questionnaire effect, with the unplanned proportion too weak to rescue it. Neither reading is settled by these trials.

Which measurements moved, and which did not?

Five measurements with published results bear on the question. The trial protocols listed many more, most of which were never reported.

What was measured	How	In whom	Result
Desire	FSFI desire domain, two questions	1,267 premenopausal women with HSDD	Up 0.30 and 0.42 over placebo, p < .001, on a 1.2 to 6 scale4
Distress about desire	FSDS-DAO item 13, one question	Same	Down 0.37 and 0.29 over placebo, p < .001 and p = .0054
Subjective arousal	FSFI arousal domain, four questions	Same, as a secondary endpoint	Reported as a categorical outcome, not as a score2
Behavior	Count of satisfying sexual events	Same	No significant difference, p = 0.76 and p = 0.701
Genital blood flow	Vaginal photoplethysmography	18 women with FSAD, 2006 pilot	No drug-placebo difference in response size, 9.6% against 14.9%, p = 0.273

Reading down that column is the quickest answer to the question in the title. Two self-report scores about desire moved. A self-report score about arousal was collected and reported without a score. Of the two measures that do not depend on what a woman reports in a questionnaire, the planned count of encounters did not move and the body did not move.

Why would a drug move desire and not arousal?

Because of where it acts. On that point, FDA is unusually candid about how little is known.

Bremelanotide is a melanocortin receptor agonist. The FDA label states that at therapeutic doses, binding to MC1R and MC4R matters most, and that "Neurons expressing MC4R are present in many areas of the central nervous system (CNS)."¹

Then comes the sentence that settles the question: "The mechanism by which VYLEESI improves HSDD in women is unknown."¹

That is a regulator declining to claim a mechanism for an approved drug. It also makes no claim anywhere of a genital vascular effect.

The vascular effects the label does document run the other way. FDA's label records that the drug "transiently increases blood pressure and reduces heart rate after each dose," and contraindicates it in uncontrolled hypertension or known cardiovascular disease.¹ Everything recorded there is systemic and framed as a risk, not as blood flow sent anywhere useful.

This matters because of how the compound is marketed. A product sold for sexual function invites the assumption that it works like the erection drugs, by opening blood vessels. On the published record it does not, and the one time anyone pointed an instrument at genital blood flow, nothing happened.

Is desire even separable from arousal in the first place?

Less than the question assumes. Most coverage skips the reason.

Two separate problems sit underneath it.

The mental and the physical are weakly linked in women. A meta-analysis in Archives of Sexual Behavior pooled 132 laboratory studies published between 1969 and 2007, covering 2,505 women and 1,918 men. Across all correlations the paper pooled, agreement averaged .56 for men and .25 for women. In the cleaner comparison, the 13 studies that tested both sexes with the same methods, it was .66 for men and .44 for women.⁷

Use the matched pair. A correlation of .44 is a real relationship and a loose one, well below the .66 in men, which still leaves considerable room for a woman's body and her experience to move separately. So a drug can change one and leave the other alone. Ordinary, not strange. Clearest demonstration of that comes from a different compound. Sildenafil was shown to increase vaginal vasocongestion in healthy premenopausal women while producing "no differences between treatments on subjective sexual arousal experience."⁸ The body responded. The experience did not.

And desire may not separate cleanly from subjective arousal either. The 2021 re-analysis makes this point against the trials, noting that "A review of the FSFI's properties suggested that the arousal and desire domains should be merged," and that "If desire is not actually a separate domain, then the FSFI-D should not be used to 'assess treatment specificity'."²

That argument cuts in both directions and the page reports it that way. It weakens any confident claim that bremelanotide moved desire specifically. It equally weakens any confident claim that it left subjective arousal untouched. What it does not do is rescue the physical arousal question, because no approval endpoint measured one.

Who were the women in the PT-141 trials?

A narrow group. Four qualifiers define it.

Participants were premenopausal, with HSDD that was acquired and generalized. The label defines both terms: "Acquired HSDD refers to HSDD that develops in a patient who previously had no problems with sexual desire," and "Generalized HSDD refers to HSDD that occurs regardless of the type of stimulation, situation or partner."¹

The indication also excludes low desire with an identifiable cause. Vyleesi's indication applies only where the problem is "NOT due to" a co-existing medical or psychiatric condition, problems with the relationship, or the effects of a medication or drug substance.¹

That last clause deserves more attention than it gets. Approved use covers low desire that remains after the common explanations are ruled out. Low desire arising from a medication, a relationship or another condition sits outside what the trials tested, by the indication's own terms.

Participants averaged 39 years old, and 85.6% were white.⁴

Does PT-141 work after menopause?

Nobody has tested it. The label says not to.

RECONNECT required participants to be premenopausal, so postmenopausal women were never in the trials.¹ The label's Limitations of Use state it directly: "VYLEESI is not indicated for the treatment of HSDD in postmenopausal women or in men."¹

Be precise here, because an untested population is not the same as a tested-and-failed one. No trial has reported that bremelanotide fails after menopause. No trial has reported anything about it after menopause. The question is open, and the approved product carries an instruction against that use.

What does this mean for a vial bought online?

Less than the trial data suggests, for three reasons that stack.

The approved product is a specific molecule at a specific dose by a specific route, 1.75 mg subcutaneously, made under manufacturing controls. A vial sold under the name PT-141 is none of those things established. Our guide on reading a certificate of analysis covers what a test on a vial does and does not establish.

Those trials also studied a diagnosed population. If the women in RECONNECT gained about a third of a point on a desire score, that figure describes premenopausal women with acquired, generalized HSDD and nobody else. It is not a result that transfers to a person with normal desire, or with low desire from a cause the trials excluded.

One side effect scales with how much you take, and an unsupervised buyer has nothing stopping them. Focal hyperpigmentation, "including involvement of the face, gingiva, and breasts, was reported in 1% of patients" who received up to 8 doses a month.¹ In a separate study, "38% of patients developed focal hyperpigmentation after receiving VYLEESI daily for 8 days," and among those who kept going for 8 more consecutive days, "an additional 14% developed new focal pigmentary changes."¹ Patients with dark skin were more likely to develop it, and "Resolution of the focal hyperpigmentation was not confirmed in all patients after discontinuation."¹

Here the melanocyte receptor from the mechanism section shows up as a visible outcome, and the rate tracks how often the drug is taken. The label recommends against more than 8 doses a month. A vial bought online comes with no such line, and nothing stops daily use.

Tolerability was poor even inside a trial. Nausea affected 40% of women on the drug against 1% on placebo, and 8% stopped taking it because of nausea.¹ Overall, 40% and 39% of women on the drug left the two trials early, against 13% and 25% on placebo.¹ In a trial, with monitoring, free product and staff to call.

What would actually settle the desire-versus-arousal question?

A study with both measures in the same women at the same time. It has not been run on the approved product.

What would answer it is not complicated. Take the approved dose by the approved route, in the approved population, and record a desire score, a subjective arousal score and a physiological genital measure together. The 2006 pilot did exactly that design, at a different dose, a different route and in a different population, with 18 women.

Three gaps keep the question open.

• No physiological measure in any Phase 3 endpoint. Not primary, not secondary, not exploratory.
• No study of the approved product with an instrument attached. The only genital measurement in the record predates the approved formulation.
• No data on the approved product outside the indicated population. Postmenopausal women have not been studied at all. The one study in women without HSDD used a different dose and route.

Until then the accurate statement is narrow. The drug moved a desire score modestly in premenopausal women with HSDD, moved a distress score, did not change the planned count of satisfying sexual events, moved an unplanned proportion of them, and has never been shown to increase physical arousal in anyone.

Common questions

Does PT-141 increase desire or arousal in women?

Does PT-141 work like Viagra?

How much did desire actually improve in the trials?

Did women in the trials have more sex?

Is PT-141 approved for women after menopause?

Is PT-141 approved for men?

What is HSDD, and does low desire mean I have it?

Why can a drug change desire without changing physical arousal?

How common is nausea with PT-141?

Is the desire score itself reliable?

Does PT-141 cause skin darkening?

Is PT-141 the same thing as Vyleesi?

What is the FSFI desire score the trials used?

How long before sex is the approved product taken?

Does any of this apply to PT-141 bought from a peptide seller?

Sources

1. VYLEESI (bremelanotide injection) prescribing information, NDA 210557. US Food and Drug Administration. accessdata.fda.gov. Read at source. Indication: "VYLEESI is indicated for the treatment of premenopausal women with acquired, generalized hypoactive sexual desire disorder (HSDD), as characterized by low sexual desire that causes marked distress or interpersonal difficulty and is NOT due to:" a co-existing medical or psychiatric condition, problems with the relationship, or the effects of a medication or drug substance. Limitations of Use, both bullets: "VYLEESI is not indicated for the treatment of HSDD in postmenopausal women or in men" and "VYLEESI is not indicated to enhance sexual performance." Definitions: "Acquired HSDD refers to HSDD that develops in a patient who previously had no problems with sexual desire"; "Generalized HSDD refers to HSDD that occurs regardless of the type of stimulation, situation or partner." Section 12.1: bremelanotide is a melanocortin receptor agonist, MC1R and MC4R binding most relevant at therapeutic doses, "Neurons expressing MC4R are present in many areas of the central nervous system (CNS)," and "The mechanism by which VYLEESI improves HSDD in women is unknown." Section 5.1: "VYLEESI transiently increases blood pressure and reduces heart rate after each dose." Section 4: contraindicated in uncontrolled hypertension or known cardiovascular disease. Section 14 co-primary endpoints: "Change from baseline to end of study (EOS) in the Desire domain from the Female Sexual Function Index (FSFI)," with "The FSFI Desire Domain score ranged from 1.2 to 6," and FSDS-DAO Question 13, "Bothered by low sexual desire?" scored 0 to 4 over a 30-day recall. Responder threshold: "at least 1.2-point increase from baseline in FSFI-Desire Domain score." Section 14 on behavior: "There was no significant difference between treatment groups in the change from baseline to end of study visit" in satisfying sexual events, p = 0.76 and p = 0.70. Section 6.1: nausea "reported in 40% of VYLEESI-treated patients compared to 1% of placebo-treated patients," highest after the first dose at 21%, with 8% discontinuing because of it. Section 14 discontinuation: "a greater percentage of MITT patients in the VYLEESI group prematurely discontinued (40% vs. 13% for Study 1 and 39% vs. 25% for Study 2)." Approval date June 21, 2019. The label PDF's table layout renders imperfectly through the retrieval tool, so the per-study assignment of the two satisfying-sexual-event p-values was checked a second way: an independent verification pass confirmed it against the structured label record and against the trial paper, which gives P=.764 for study 301 and P=.702 for study 302. The assignment above is correct.
2. Spielmans GI. Re-Analyzing Phase III Bremelanotide Trials for "Hypoactive Sexual Desire Disorder" in Women. J Sex Res 2021;58(9):1085-1105. doi:10.1080/00224499.2021.1885601. newsroom.taylorandfrancisgroup.com. Read via the publisher's own hosted PDF; the journal's full-text page returned an error. An independent re-analysis of the Phase 3 data using FDA review documents. "In terms of number of satisfying sexual events, bremelanotide provides no benefit." "42.1% of bremelanotide participants not completing a study compared to 20.48% of participants taking placebo." "Bremelanotide offers little benefit for women diagnosed with HSDD." "Kingsberg et al.'s data reporting and measurement practices were incomplete and lacked transparency." On the instrument: "A review of the FSFI's properties suggested that the arousal and desire domains should be merged," and "If desire is not actually a separate domain, then the FSFI-D should not be used to 'assess treatment specificity'." On the behavioral measures, Table 4 gives the percentage of sexual encounters rated satisfactory as an improvement of 25.0% on bremelanotide against 9.8% on placebo, p < .001, marks the diary-derived outcomes as not prespecified in the registration, and the text states "it seems these outcomes were concocted post-hoc." Table 2 lists the FSFI arousal domain, items 3 to 6, as a secondary outcome "Presented as categorical outcome." The recomputed desire difference is given as .36 units, close to the trial paper's integrated 0.35. The discontinuation figures differ slightly from the FDA label's, which this page quotes instead, because the two use different denominators; the label is the stronger source for the regulatory record and the re-analysis found rates a few points higher.
3. Diamond LE, Earle DC, Heiman JR, Rosen RC, Perelman MA, Harning R. An Effect on the Subjective Sexual Response in Premenopausal Women with Sexual Arousal Disorder by Bremelanotide (PT-141), a Melanocortin Receptor Agonist. J Sex Med 2006;3(4):628-638. doi:10.1111/j.1743-6109.2006.00268.x. kinseyinstitute.org. Read via a reproduction of the published article hosted by a co-author's institution; the publisher's own page could not be opened. "Randomized, double-blind, placebo-controlled crossover pilot study" in eighteen premenopausal women aged 22 to 44 with a primary diagnosis of female sexual arousal disorder, requiring an FSFI arousal domain score below 3 and a Female Sexual Distress Scale score above 40, and "a previous history of a normal and satisfying sexual response." Single intranasal 20 mg dose. The paper lists two main outcome measures, not one: "Change in vaginal pulse amplitude during neutral and erotic videos after treatment with bremelanotide or placebo" and subjects' perceptions of physiological and sexual response within 24 hours of treatment. Vaginal pulse amplitude was measured by vaginal photoplethysmography. Result: maximum amplitude change 9.6% (SD 13.3) on bremelanotide against 14.9% (SD 17.1) on placebo, P = 0.27. Abstract, quoted in full because a truncation at "erotic videos" reverses the meaning: "Vaginal vasocongestion did not change significantly while viewing erotic videos following bremelanotide administration compared with placebo." The erotic videos did produce a vasocongestion response; what did not differ was drug against placebo. The 9.6% and 14.9% figures are maximum amplitude change, peak pulse amplitude during the erotic video relative to the neutral one, not levels of blood flow. Subjective desire: 67% against 22%, P = 0.0114. Among women who had sex within 24 hours, significantly more were satisfied with their level of arousal after bremelanotide, P = 0.0256. Reported feelings of genital arousal: 72% against 39%, P = 0.0833, not significant. Conflict of interest: "Lisa E. Diamond, Dennis C. Earle, and Ronald Harning are employees of Palatin Technologies."
4. Kingsberg SA, Clayton AH, Portman D, Williams LA, Krop J, Jordan R, Lucas J, Simon JA. Bremelanotide for the Treatment of Hypoactive Sexual Desire Disorder: Two Randomized Phase 3 Trials. Obstet Gynecol 2019;134(5):899-908. doi:10.1097/AOG.0000000000003500. PMID 31599840. Abstract read via a reproduction of the indexed record; the full text could not be opened, so the Methods, secondary-endpoint tables and figures were not read for this page. Co-primary endpoints: "change from baseline to end-of-study in the Female Sexual Function Index-desire domain" and "Female Sexual Distress Scale-Desire/Arousal/Orgasm item 13." Between-group differences in desire: "study 301: 0.30, P<.001; study 302: 0.42, P<.001; integrated studies 0.35, P<.001." Distress: "study 301: -0.37, P<.001; study 302: -0.29, P=.005; integrated studies -0.33, P<.001." Population: "Of the 1,267 women randomized, 1,247 and 1,202 were in the safety and efficacy (modified intent-to-treat) populations," randomized "1:1 to 24 weeks of treatment," and "Most participants were white (85.6%), from U.S. sites (96.6%), and had a mean age of 39 years." The trial registration numbers appear in the FDA label as NCT02333071 and NCT02338960. An independent verification pass confirmed the paper states the mapping directly, study 301 to NCT02333071 and study 302 to NCT02338960, and that the label identifies NCT02333071 as Study 1, so label Study 1 is the paper's study 301.
5. Rosen R, Brown C, Heiman J, Leiblum S, et al. The Female Sexual Function Index (FSFI): a multidimensional self-report instrument for the assessment of female sexual function. J Sex Marital Ther 2000;26(2):191-208. doi:10.1080/009262300278597. PMID 10782451. Journal, year, volume, issue, pages, DOI and PMID verified against the OpenAlex metadata registry. Text read via a reproduction hosted by a co-author's university laboratory; the publisher's page could not be opened. Nineteen items across six domains: desire (2 items), arousal (4), lubrication (4), orgasm (3), satisfaction (3), pain (3). The arousal domain items ask how often the respondent felt "sexually aroused ('turned on') during sexual activity or intercourse," how she would rate that level, how confident she was about becoming aroused, and how often she was satisfied with her arousal. The desire domain scores from 1.2 to 6.0 because its two items are scored 1 to 5 with no zero option, giving a usable range of 4.8 points; the other domains floor at zero. The retrieval of this PDF required normalizing letter-spacing artifacts in its text layer, so the item wording is the paper's but the spacing is reconstructed, and the canonical instrument text was not retrieved.
6. Rao TSS, Andrade C. Bremelanotide for Hypoactive Sexual Desire Disorder. J Psychosexual Health 2020;2(1):13-15. doi:10.1177/2631831820909450. Read at source. A commentary, not original data. States that "bremelanotide produces only small benefits, in the average patient," reports the pooled desire superiority as 0.3 points with an effect size of 0.39 and the distress superiority as 0.33 points with an effect size of 0.27, and gives a response rate of 58% against 35% for drug against placebo.
7. Chivers ML, Seto MC, Lalumière ML, Laan E, Grimbos T. Agreement of self-reported and genital measures of sexual arousal in men and women: a meta-analysis. Arch Sex Behav 2010;39(1):5-56. doi:10.1007/s10508-009-9556-9. link.springer.com. Abstract and results section both read at source. "We identified 132 peer- or academically-reviewed laboratory studies published between 1969 and 2007 with total sample sizes of 2,505 women and 1,918 men." The abstract's headline pair is "men (r = .66) showing a greater degree of agreement than women (r = .26)," and this page deliberately does not use it. Checked against the results section, that pair mixes two analyses: the pooled figures across all correlations are .56 for men (95% CI .50 to .62, 184 correlations) and .25 for women (95% CI .21 to .28, 280 correlations), while the 13 studies that tested both sexes produced 17 independent samples per sex, 375 men and 424 women, giving .66 for men (95% CI .49 to .83) and .44 for women (95% CI .30 to .57). The value .26 does not appear anywhere in the results as a women's correlation; it occurs once as a confidence bound in an unrelated subgroup. This page uses the pooled pair and the matched pair, both labeled, because the matched comparison is the only one that holds method and stimulus constant across sexes and it roughly halves the gap the abstract implies.
8. Laan E, van Lunsen RHW, Everaerd W, Riley A, Scott E, Boolell M. The Enhancement of Vaginal Vasocongestion by Sildenafil in Healthy Premenopausal Women. J Womens Health Gend Based Med 2002;11(4):357-365. doi:10.1089/152460902317585994. Abstract read at source; the full text is restricted. Twelve healthy premenopausal women without sexual dysfunction, single 50 mg oral dose. "Significant increases in vaginal vasocongestion were found with sildenafil treatment compared with placebo." "There were no differences between treatments on subjective sexual arousal experience." One complication the abstract adds and this page notes rather than omits: analyzed by which treatment the women believed they had received, they reported significantly stronger arousal and wetness for the session they thought was sildenafil, and the treatment sequence was guessed incorrectly by half of them. Subjective arousal did move; it tracked belief rather than assignment. Cited here as a published demonstration that a drug can move a genital measure without moving a subjective one by assignment, with that caveat attached.

Sources that could not be read for this page

• The three Reddit threads supplied with this brief, in r/Biohacking and r/BiohackingU. Reddit is blocked to the tools used for this page and was not read through any cache or mirror. No thread content is asserted anywhere above.
• The full text of the Phase 3 paper, behind a publisher error and a CAPTCHA on the indexing services. Only the abstract was read, so the Methods, the secondary-endpoint tables and the figures did not inform this page. The FDA label supplied the endpoint detail instead.
• The registry record for the second Phase 3 trial, robots-disallowed, so no posted secondary results were read for it.
• The publisher's page for the 2006 pilot and for the sildenafil study, both restricted. The pilot was read via a co-author's institutional copy; the sildenafil study only as an abstract.
• DSM-5 itself, paywalled. No diagnostic criteria are quoted from it on this page.