Vyleesi (Bremelanotide) Monitoring for Adults 30 to 49: Blood Pressure, Side Effects, and Follow-Up Schedule

What does the Vyleesi label actually ask you to monitor?

Vyleesi is a melanocortin receptor agonist that activates several receptor subtypes, with binding at MC1R and MC4R the most relevant at therapeutic doses; how it improves sexual desire is unknown [1]. It is self-injected under the skin of the abdomen or thigh, as needed, at least 45 minutes before anticipated sexual activity, no more than once in 24 hours; more than 8 doses a month is not recommended [1]. It has no boxed warning and no risk evaluation and mitigation strategy [1][2].

The label's monitoring content is short and specific. The Vyleesi label says to consider cardiovascular risk and ensure blood pressure is well controlled before treatment and periodically while treatment continues [1]. The dosing section adds a time limit on judging benefit: stop after 8 weeks if there is no improvement in symptoms [1]. Side-effect review fills in the rest, and the three the label highlights are blood pressure and heart rate, focal hyperpigmentation, and nausea [1].

The two phase 3 trials included women aged 19 to 56, with a mean age of 39 [1]. The label does not vary its instructions by age; they apply to the premenopausal population it studied [1].

Blood pressure: how large is the rise, and how long does it last?

The figures most often quoted for Vyleesi are maximal increases, not averages. In clinical studies the drug produced maximal increases of 6 mmHg systolic and 3 mmHg diastolic, peaking between 2 and 4 hours after the dose, with a heart rate reduction of up to 5 beats per minute; blood pressure and heart rate usually returned to baseline within 12 hours [1]. Repeat daily dosing 24 hours apart for up to 16 days produced no additive effect on blood pressure or heart rate [1].

The average effect is smaller. In an open-label ambulatory blood pressure study of 127 premenopausal women dosed once daily for 8 days, the mean daytime increase was 1.9 mmHg systolic (95% CI 1.0 to 2.7) and 1.7 mmHg diastolic (95% CI 0.9 to 2.4), with a mean heart rate decrease of 0.5 beats per minute [1]. Peak effects in that study were 2.8 mmHg systolic between 4 and 8 hours after dosing and 2.7 mmHg diastolic between 0 and 4 hours, and readings at 12 to 24 hours after a dose were similar to pre-dose values [1].

Who the label says should not use it

The label lists uncontrolled hypertension and known cardiovascular disease as contraindications [1]. It also states that Vyleesi is not recommended for patients at high risk for cardiovascular disease, and repeats that cardiovascular risk should be weighed and blood pressure well controlled both before starting and periodically during treatment [1]. It does not give a number for well-controlled blood pressure [1].

Nausea: the most common reaction and the top reason women stopped

Nausea was reported by 40.0% of Vyleesi-treated women versus 1.3% on placebo in the pooled phase 3 trials; 13% of treated patients received an anti-nausea medicine and 8% stopped the trials because of it [1]. The median onset was within 1 hour of a dose and it lasted about 2 hours [1]. Incidence was highest after the first dose, reported by 21% of patients, then fell to about 3% after later doses [1]. The label says nausea improves for most patients with the second dose and suggests considering stopping Vyleesi for persistent or severe nausea, or starting an anti-nausea medicine for patients bothered by it who want to continue [1].

One practical point runs against a common assumption. In a phase 4, single-dose, placebo-controlled study of 228 healthy women, taking 8 mg of oral ondansetron 30 minutes before a 1.75 mg dose did not reduce the incidence of nausea, and the label therefore does not recommend pre-treatment with oral ondansetron [1]. Ondansetron given after Vyleesi or after nausea begins has not been formally studied [1].

Focal hyperpigmentation

Vyleesi binds MC1R on pigment cells, which increases pigmentation [1]. In the placebo-controlled trials, focal hyperpigmentation, including the face, gums and breasts, was reported by 1% of patients receiving up to 8 doses a month versus none on placebo [1]. Daily dosing raises the risk sharply: 38% of patients developed focal hyperpigmentation after 8 days of daily dosing, and a further 14% developed new pigmentary changes after 8 more consecutive days [1]. Darker skin carries a higher risk [1].

Resolution was not confirmed in all patients after the drug was stopped, and the label says to consider discontinuing Vyleesi if hyperpigmentation develops [1]. This is also one of the reasons more than 8 doses a month is not recommended, since more frequent dosing increases both the risk of hyperpigmentation and the number of days each month that blood pressure is raised [1].

Injection sites and the other common reactions

Injection site reactions were reported by 13.2% of Vyleesi patients versus 8.4% on placebo; the label's list behind that figure includes pain, erythema, hematoma, pruritus, hemorrhage, bruising, paresthesia and hypoesthesia [1]. Other reactions reported in at least 2% of treated patients and more often than placebo were flushing (20.3% vs 0.3%), headache (11.3% vs 1.9%), vomiting (4.8% vs 0.2%), cough (3.3% vs 1.3%), fatigue (3.2% vs 0.5%), hot flush (2.7% vs 0.2%), paresthesia (2.6% vs 0.0%), dizziness (2.2% vs 0.5%) and nasal congestion (2.1% vs 0.5%) [1]. The label says the majority of events were mild (31%) to moderate (40%) in intensity and transient [1].

Serious adverse reactions occurred in 1.1% of Vyleesi patients versus 0.5% on placebo, and 18% versus 2% stopped treatment because of an adverse reaction, most often nausea (8%), headache (2%), vomiting (1%), flushing (1%) or injection site reactions (1%) [1].

The 8-week checkpoint and follow-up after it

For assessing benefit, the label says to stop Vyleesi after 8 weeks if symptoms have not improved [1]. Efficacy in the trials was measured with the Female Sexual Function Index desire domain and the Female Sexual Distress Scale-Desire/Arousal/Orgasm item 13 [3]. Across the two trials, desire scores improved by 0.30, 0.42 and 0.35 integrated points versus placebo, and desire-related distress fell by 0.37, 0.29 and 0.33 points [3]. There was no significant difference in the number of satisfying sexual events [3].

Longer-term data come from a 52-week open-label extension: of 856 women who completed the core phase, 684 enrolled and 272 completed it, with nausea (40.4%), flushing (20.6%) and headache (12.0%) the most common drug-related events [4]. That extension had no placebo group and its analyses were descriptive [4].

Liver, pregnancy and drug interactions

One case of acute hepatitis occurred in the open-label extension, in a patient who had received 10 doses over a year and presented with transaminases above 40 times the upper limit of normal, bilirubin 6 times the upper limit and alkaline phosphatase under 2 times the upper limit; liver tests normalized 4 months after the drug was stopped, and because no other cause was found a role for Vyleesi could not be excluded [1].

The label directs patients to stop Vyleesi if pregnancy is suspected and to use effective contraception while taking it, based on animal findings of fetal harm at exposures at least 16 times the human dose by AUC [1]. A labeling supplement approved on October 22, 2026 revises the Use in Specific Populations section and the patient information [5].

Vyleesi may slow stomach emptying and reduce absorption of oral medicines; the label says to avoid it with oral drugs that depend on threshold blood concentrations, such as antibiotics, and to consider skipping a dose when a rapid effect from an oral medicine such as indomethacin is wanted [1]. The label says to avoid Vyleesi with oral naltrexone products used for alcohol or opioid addiction, because Vyleesi may significantly decrease naltrexone exposure and treatment failure is a serious consequence [1]. In a crossover study of 24 healthy volunteers, alcohol at 0.6 g/kg did not change bremelanotide blood levels, though that study used a 20 mg intranasal dose with about 2.5-fold the peak concentration of Vyleesi [1].

Is this the same as compounded PT-141?

The FDA-approved bremelanotide product is Vyleesi; PT-141 products sold as compounded or research-use peptides are not Vyleesi and are not FDA-approved drugs, and compounded drugs are not reviewed by FDA for safety, effectiveness or quality before marketing [1][6].