How quickly does PT-141 work?

PT-141 (Vyleesi) typically begins to take effect within 45 minutes of subcutaneous injection, with peak effects occurring approximately 2-4 hours after administration. This is in contrast to flibanserin (Addyi), which requires weeks of daily dosing. The as-needed dosing model allows women to use PT-141 in anticipation of sexual activity.

Does PT-141 work for men?

Early clinical trials demonstrated that PT-141 could produce erections in men with erectile dysfunction, including some who did not respond to PDE5 inhibitors like Viagra. However, the development program for male ED was discontinued due to the side effect profile and competitive landscape. PT-141 is only FDA-approved for premenopausal women with HSDD, and off-label use in men should only occur under physician supervision.

Is PT-141 the same as Melanotan 2?

No. PT-141 (bremelanotide) was derived from Melanotan II but is a distinct compound with a different chemical structure and receptor selectivity profile. PT-141 was optimized for MC4R activity (sexual function) with reduced MC1R activity (tanning). Melanotan II has broader melanocortin receptor activity, stronger tanning effects, and a more significant side effect profile. PT-141 is FDA-approved; Melanotan II is not.

What are the most common side effects of PT-141?

The most common side effect is nausea, affecting approximately 40% of patients in clinical trials. Other common side effects include flushing (about 20%), headache (about 11%), injection site reactions, and potential skin darkening with repeated use. PT-141 also causes a transient increase in blood pressure. These side effects are generally self-limiting but can be significant enough to limit regular use for some patients.

Can I use PT-141 daily?

No. The Vyleesi prescribing information limits use to no more than one dose per 24 hours and no more than 8 doses per month. These restrictions reflect concerns about cumulative blood pressure effects and the risk of skin hyperpigmentation with frequent dosing. PT-141 is designed as an as-needed medication, not a daily treatment.

Is PT-141 covered by insurance?

Insurance coverage for Vyleesi varies significantly by plan. Many insurance plans do not cover HSDD treatments, and out-of-pocket costs for Vyleesi can be substantial. Palatin Technologies and AMAG Pharmaceuticals have offered patient assistance programs. Compounded PT-141 from specialty pharmacies may be less expensive but does not carry the same quality assurance as the branded product.

Does PT-141 cause permanent skin darkening?

Skin hyperpigmentation from PT-141 can occur with repeated use, particularly on the face, gums, and breasts. In clinical trials, the darkening was generally reversible upon discontinuation, but the time course for resolution varied. Patients should be monitored for skin changes and discuss any concerns with their prescribing physician.

Vendor Rankings

Independent rankings of peptide vendors based on aggregated lab data, COA transparency, community sentiment, and verified pricing. We publish everything — including the failures.

108+ samples tracked 93 vendors ranked 15 peptides tracked

All BPC-157 Tirzepatide Semaglutide CJC-1295 Ipamorelin GHK-Cu Retatrutide Tesamorelin

AGreat

B+Very Good

BGood

COkay

DPoor

EBad

FFraud

PT-141 Rankings

FDA-APPROVED

108 samples across 93 vendors · Updated weekly from independent lab testing

#	Vendor	Avg score	Purity range	Tests	Verified $/mg	Grade	Profile
Grade B+ — Very Good
1	Reta-Peptide	7.5	—	5	—	B+	review →
Grade B — Good
2	Uther	7.5	—	4	—	B	review →
3	HK Peptides	7.4	—	7	—	B	review →
4	Allen Biotechnology Co ABC	7.3	—	4	—	B	review →
5	LiliPeptide	7.2	—	9	—	B	review →
6	Bulk Peptide Wholesale	7.1	—	3	—	B	review →
7	Orbitrex Peptides	6.9	—	2	—	B	review →
8	Bulk Peptide Supply	6.7	—	2	—	B	review →
9	Oupeptide	6.6	—	4	—	B	review →
Grade C — Okay
10	Qing Li Peptide	6.5	—	6	—	C	review →
11	SRY Labs	6.3	—	2	—	C	review →
12	NuLife Peptides	5.9	—	2	—	C	review →
13	Peptidology	5.8	—	4	—	C	review →
14	Wuhan Wansheng Biotechnology	5.8	—	4	—	C	review →
15	Biolongevity Labs	5.6	—	3	—	C	review →
16	Shanghai Sigma Audley SSA	5.3	—	5	—	C	review →
17	Pure Tested Peptides	5.1	—	2	—	C	review →
18	Polaris Peptides	5.1	—	8	—	C	review →
19	Planet Peptide	5.0	—	3	—	C	review →
20	Paramount Peptides	5.0	—	3	—	C	review →
Grade D — Poor
21	Peptide Technologies	4.8	—	2	—	D	review →
22	Biolabshop Limited	4.8	—	2	—	D	review →
23	Pharma Grade Peptides	4.8	—	2	—	D	review →
24	Verified Peptides	4.7	—	4	—	D	review →
25	Atomik Labz	4.7	—	4	—	D	review →
26	Nuscience Peptides	4.3	—	2	—	D	review →
27	Science	4.3	—	2	—	D	review →
28	Peptide Gurus	4.0	—	3	—	D	review →
29	Deuschem	3.5	—	4	—	D	review →
Grade F — Fraud
30	Amino Asylum	—	—	1	—	F	review →
31	Shaanxi Xianhe Biotech	—	—	0	—	F	review →
32	ZLZ Peptide	—	—	0	—	F	review →
33	Zhengzhou Lan Yun Cosmetic Trading	—	—	0	—	F	review →
34	ZePeptide	—	—	0	—	F	review →
35	Yiwu Aozuo Trading Co	—	—	0	—	F	review →
36	Xingtai Jiachuang Technology	—	—	0	—	F	review →
37	VIP Wellness Access	—	—	0	—	F	review →
38	Guangzhou Yuao Trading	—	—	0	—	F	review →
39	Shanghai Wibson Biotechnology WBS	—	—	0	—	F	review →
40	Chameleon Peptides	—	—	0	—	F	review →
41	Crest Limited	—	—	0	—	F	review →
42	Peptide CHN	—	—	0	—	F	review →
43	Mammoth Muscle Peptides	—	—	0	—	F	review →
44	Laicuinuo LCN	—	—	0	—	F	review →
45	Homopeptide	—	—	0	—	F	review →
46	10 Bottle Value	—	—	0	—	F	review →
47	Peptide Makers	—	—	0	—	F	review →
48	LP Peptide	—	—	0	—	F	review →
49	Jinzhou hongbai technology	—	—	0	—	F	review →
50	Tianjin Eleli Technology Development	—	—	0	—	F	review →

Verified $/mg = list price ÷ (avg tested qty / labeled qty). Vendors below the cutoff omitted from view.