Hormones and Libido Stack: PT-141, Oxytocin, Kisspeptin, hCG and the Crave Blend

What is the hormones and libido stack?

The hormones and libido stack is two different combinations. On the libido side, people take PT-141 with oxytocin, sometimes with kisspeptin, before sex, from separate vials or blends such as Crave and Love & Happiness. On the hormone side, men on testosterone therapy add hCG, gonadorelin or kisspeptin. No trial has tested the libido parts together, or the hormone parts together during testosterone therapy. [7], [1]

PT-141 is approved for low desire in premenopausal women, oxytocin and hCG for other uses, gonadorelin only in some countries, and kisspeptin in none of the countries we checked. [9], [10], [12], [13], [18]

The two sides rarely meet: the libido parts are taken as needed, sometimes with tadalafil, a prescription erection drug that is not a peptide, while the hormone parts are injected weekly, usually one in place of another.

What's in it, and what else is it called?

The libido side is PT-141, oxytocin and kisspeptin. The hormone side is hCG and gonadorelin, with kisspeptin as an alternative. Only the libido side is sold premixed: we found no public premix of hCG with gonadorelin. [17]

A blend's name does not fix what is in the vial. Crave is listed with 2 mg or 10 mg of kisspeptin-10, and PT-141/oxytocin blends flip the ratio between sellers. [2], [4], [5]

What is in each blend in this stack?

Only the libido side is sold premixed: PT-141 and oxytocin blends, Love & Happiness, and Crave and IM Libido, which add kisspeptin. No blend has been tested in people, and no regulator notice names any of them.

Amounts below are what labels state. They are not doses, and not proof of contents. Where a page doses in "units" without naming the syringe, we assume insulin-syringe units of 0.01 mL; the pages do not say.

PT-141 and oxytocin blends

PT-141 with oxytocin, the pairing people in community education groups most often combine.

• Where sellers disagree: the ratio flips between 1:2 and 2:1, and per-spray amounts do not add up: XO Blend lists 3 mcg of PT-141 a spray, the Akira spray about 31 mcg, and the Akira page prints "mg" where it means micrograms. [4], [19]
• What oxytocin is claimed to add: bonding and closeness. Its guide finds no good evidence for sexual function: in the largest trial, women with sexual problems improved by 26% on oxytocin and 31% on placebo. [20]
• Stated amounts: 2, 4 or 6 sprays, 2–3 times a week (see combination schedules). [19]
• Regulators: none names these blends; FDA warned "research" PT-141 sellers, including Peptide Partners, in August 2026. [21]

Love & Happiness

Oxytocin 50 mg + PT-141 10 mg per 5 mL, from a supplier catalog for licensed providers and a clinic menu that agree; no route is stated. [1], [2]

• Stated amounts: start at 10 units, rise to 25 and "use 5x per week", or 25–30 units 30–60 minutes before sexual or social activity; the same text also says "as needed, 1-5x weekly". [1]
• What that would hold: at 25–30 units, 2.5–3 mg of oxytocin (about 1,500–1,800 IU), 5–30 times the 100–500 mcg injections that public forum reports link to flushing and near-fainting, but only about a third of PT-141's labeled 1.75 mg. [22], [23], [24], [9]

Crave

Love & Happiness plus kisspeptin-10, sold as a "three-pathway" formula. [1]

• Where sellers disagree: kisspeptin differs fivefold. The catalog's Crave dosing text is copied word for word from Love & Happiness, so the same oxytocin arithmetic applies. [1]
• What kisspeptin is claimed to add: "hormone-driven" desire. Its guide's best evidence is single IV infusions of the longer kisspeptin-54, which changed brain responses to sexual images. Kisspeptin-10 clears in about 4 minutes and is normally used on a schedule, not as needed. [25], [26], [27]
• Regulators: none names Crave; kisspeptin is on FDA's compounding safety-risk list. [18]

IM Libido

PT-141 1 mg + kisspeptin 2 mg + oxytocin 0.9 mg per 3 mL, for subcutaneous injection: kisspeptin is the largest part, the reverse of Crave. The page suggests 30 units a day, 2–5 times a week, in 4–8-week cycles "or situationally as needed". No regulator notice names it. [3]

Troches and sprays with tadalafil

Many libido products are compounded troches or sprays that add tadalafil, a prescription erection drug that is not a peptide, such as the Olympus troche (oxytocin 20 IU + PT-141 1 mg, plus tadalafil 20 mg for men) and Elate spray. Some leave PT-141 out. Any effect cannot be credited to the peptides. [15], [14], [28]

Other names you may see

The same catalog's Empress blend holds kisspeptin-10 with MOTS-c, BPC-157 and GHK-Cu, which is not this stack. Its other parts are covered in the mitochondrial, healing and recovery and skin and hair stacks. [1]

Why do people combine these peptides?

People combine the libido parts because they act through different systems, and the hormone parts to keep the testicles working on TRT. That reasoning comes from separate studies of each part, not from tests of the combinations.

• "Different pathways" (libido side). Sellers describe PT-141 for desire, oxytocin for bonding and kisspeptin for "hormone-driven" desire. PT-141 and oxytocin act on different receptors, so a blend adds a second drug rather than strengthening one. [1], [9]
• Blood flow. Tadalafil is added for erections, with PT-141 for desire. [14] In community education groups, people often called combination troches mild, and some found tadalafil alone as good.
• Testicles on TRT (hormone side). Testosterone therapy switches off the signals that keep the testicles working, and hCG stands in for them. Since US compounding of hCG was restricted in March 2020, some clinics use gonadorelin instead, or add or swap in kisspeptin. [29], [30], [31], [17]

What does the evidence show?

No trial has tested the libido parts together, or the hormone parts together during testosterone therapy. Only PT-141 and hCG have been tested with repeated use toward this stack's goals; kisspeptin has single-infusion laboratory trials.

PT-141

Two 24-week trials in 1,247 premenopausal women found small gains in desire and less distress, with no increase in satisfying sexual events. [32], [9] In men, small laboratory studies and one 342-man trial of a nasal spray measured erections, not desire; that trial's paper now carries an expression of concern, and PT-141 is not approved for men. [33], [34], [35], [9] Full PT-141 evidence

Oxytocin

No good evidence for sexual function: the largest nasal trial in women was negative, and single doses did not change arousal in healthy women or men. No human study has tested the injections sold online. [20], [36], [37] Full oxytocin evidence

Kisspeptin

Single IV infusions of kisspeptin-54 changed brain responses to sexual images in 32 women and 32 men with low desire. In the men, it also increased erection swelling during the images by up to 56% compared with placebo. [25], [26] No study has tested repeated doses or the kisspeptin-10 injections sold online. [25], [26] Full kisspeptin evidence

hCG

In a 3-week trial in 29 men given testosterone, 250–500 IU every other day kept testosterone inside the testicles near its starting level; 26 men on TRT kept stable semen results. No trial has tested pregnancy rates. [29], [38] Full hCG evidence

Gonadorelin

No study has tested the injections TRT clinics use. In short hormone studies, testosterone blunted the pituitary's response even to pump-sized pulses of GnRH. [39] Full gonadorelin evidence

The combination

• Libido parts together: nothing. We found no human or animal study of PT-141, oxytocin and kisspeptin in any pair.
• PT-141 with a Viagra-type drug. In 19 men with erection problems, nasal PT-141 plus sildenafil gave stronger erections than sildenafil alone. That was not injected PT-141, tadalafil or a desire outcome. [40]
• Gonadorelin with hCG, outside TRT. Studies from 1997 to 2003 gave gonadorelin as a nasal spray, followed by or alongside hCG, to boys with undescended testicles. In a 324-boy comparison, the testicle moved down in 34.5% on hCG, 29.4% on gonadorelin and 29.6% on both; a 155-boy study found no difference between regimens. Guidelines now advise against hormones for this. [7], [8], [41], [42], [43], [44] In fertility treatment, women given gonadorelin pulses to bring on ovulation received hCG afterwards to support the rest of the cycle, a use unrelated to this stack. [6]
• Hormone side on TRT: nothing. No study has tested hCG with gonadorelin or kisspeptin during TRT.
• Hormone links, not treatments. One IV kisspeptin injection raised blood oxytocin by about 19% in 12 adults; an 8-hour oxytocin infusion did not change LH pulses. [45], [46]

How do the hormones and libido stack protocols line up?

These are the rows from each part's guide that match how the stack is used: a label for PT-141, the US guideline for hCG, and protocol websites for the rest. Oxytocin injections of 100–500 mcg come from websites and forum reports, and no human study has tested them. None of the rows is a stack protocol. [47], [23], [24]

Schedules published for the combination

Each row is a complete schedule from one page, with that page's amounts kept together. Both contain PT-141 and oxytocin; Elate also contains tadalafil.

What one stated dose of each vial blend contains

Arithmetic from each vial's listed contents at the pages' stated units, assuming 0.01 mL a unit. Not a dose.

How people line them up

The libido parts are taken together 30–60 minutes before sex [1], [19], [47], although PT-141's blood pressure effect peaks 2–4 hours after a dose and oxytocin clears within minutes. Kisspeptin, hCG and gonadorelin normally follow their own schedules. [9], [10], [48], [49], [31]

These schedules come from a label, a guideline and protocol websites for each part; no trial has tested this combination.

Plan it once. An as-needed peptide with a monthly cap next to weekly hormone injections is easy to mix up.

What are the overlapping risks and interactions?

The main shared risks are blood pressure and heart-rate swings, nausea and flushing, water retention and effects on fertility. Blends dosed in undefined units can hide a large oxytocin dose. [9], [10], [12]

• Blood pressure and heart rate. PT-141 raises blood pressure after every dose (up to 6/3 mmHg on average) and is not for uncontrolled high blood pressure or heart disease. Public forum reports link oxytocin injections of 100–500 mcg to flushing, a pounding heart and near-fainting. How they add up with each other and with tadalafil has not been studied. [9], [23], [24]
• Nausea and flushing. In PT-141's trials, 40% had nausea and 20% flushing; gonadorelin's label lists both as rare. [9], [13]
• Water and sodium. Oxytocin makes the kidneys hold water, and dangerously low sodium has followed heavy nasal use combined with large IV fluid volumes; hCG's label lists fluid retention. [10], [50], [12]
• Skin darkening. With daily PT-141, 38% developed dark patches within 8 days. The label's 8 doses a month is far below blend schedules of "5x per week" or 2–5 times a week. Those blend doses hold less PT-141 each time; whether frequent small doses darken skin has not been studied. [9], [1], [3]
• Long erections. Most online reports of erections lasting too long involve PT-141 with tadalafil; an erection lasting more than four hours is an emergency. [51], [52], [53]
• Working against each other on TRT, in theory. Testosterone and the estradiol made from it blunt the pituitary's response to GnRH-sized pulses, which is where kisspeptin and gonadorelin act [39], and hCG raises both [38], [54]. This has not been studied.
• Wrong contents. Multi-peptide vials are harder to test, and in one lab test, 6 of 16 illegal "hCG" products held none. [55]

Interactions. No interaction between the parts has been studied. PT-141 lowers oral naltrexone levels (avoid the pair); oxytocin needs care with drugs that affect heart rhythm; sex hormones, clomiphene and dopamine-blocking drugs change gonadorelin's effect; hCG can make pregnancy and LH tests read wrongly. [56], [57], [13], [58], [59]

Be especially cautious or avoid them with high blood pressure, heart disease or a long QT interval; low sodium or seizures; pregnancy, trying to conceive or breastfeeding; a pituitary tumour (gonadorelin) or prostate cancer (hCG); naltrexone; and tested sport. On TRT, hCG is not proven to protect fertility. [9], [57], [60], [13], [12], [61]

Legal and sport status (checked September 2026):

• United States: PT-141 is approved only as Vyleesi, oxytocin for labor and hCG as a prescription biologic. No human gonadorelin product is sold in the US (Factrel and Lutrepulse were discontinued), none was ever approved for use with TRT, and kisspeptin is on FDA's compounding safety-risk list. FDA warned "research" sellers of PT-141 and gonadorelin in 2026. [9], [21], [10], [30], [62], [63], [18]
• Canada: Health Canada seized PT-141, gonadorelin and kisspeptin as unauthorized injectable peptides in 2025; oxytocin and hCG are prescription medicines. [64], [65], [66]
• Australia: oxytocin, hCG and gonadorelin are prescription-only (Schedule 4); PT-141 and kisspeptin have no named entry, but the regulator has argued in court that bremelanotide is already prescription-only, and kisspeptin may fall under the Schedule 4 "hypothalamic releasing factors" group. [67], [68], [69]
• Sport: WADA bans kisspeptin, hCG and gonadorelin for male athletes at all times, so Crave and IM Libido are banned for men; PT-141 and oxytocin are not named. [70]

What should be monitored?

No official guidance covers the combination. What the parts' labels, guidelines and trials measured:

• Blood pressure and heart: before starting and periodically on PT-141; heart rate and rhythm in oxytocin trials. [9], [71]
• Blood work: sodium with frequent or large oxytocin doses; on TRT, testosterone, estradiol, LH and FSH, with the first check no sooner than 4 weeks after starting hCG. hCG can read as LH on some tests. [10], [49], [58]
• Sperm: a semen analysis if fertility matters. [61]
• Skin: new dark patches on the face, gums or breasts. [9]
• Response and side effects: desire and satisfying events, as in the PT-141 trials, plus nausea, flushing and headache. [32], [9]

With a blend, a reaction cannot be traced to one part. Stop and talk to a clinician before restarting anything.

What happens when you stop?

Little is known about stopping any part, and nobody has studied stopping one part while continuing another.

• PT-141: the blood pressure rise fades within about 12 hours, but dark patches may not fade. [9]
• Oxytocin and kisspeptin: both clear from the blood within minutes; no withdrawal effect is described. [10], [27]
• hCG on TRT: stopping leaves the testicles with TRT alone; in the 3-week trial, TRT alone cut testosterone inside them by 94%. [29]
• Gonadorelin: it clears in about 4 minutes, and stopping it on TRT has not been studied. [13]

Premixed blend or separate vials?

A blend is one injection or spray, but it fixes the ratio, forces one schedule on parts meant for different ones, and hides which part caused a side effect. Separate vials take more steps but keep each dose adjustable and traceable.

• Mixing and stability. No published study shows whether these peptides stay stable mixed in one vial, spray or troche. FDA notes that kisspeptin-10 can be "extremely sensitive to product formulation, process, and environmental conditions", including pH, heat and concentration. [11]
• The ratio is locked. In Crave and Love & Happiness, oxytocin is five times PT-141 by weight. Reaching PT-141's labeled 1.75 mg from that vial would take about 88 units, which also hold about 8.8 mg of oxytocin; halving the dose because of flushing also halves PT-141. [1], [9]
• Schedules and tracking. PT-141 is as needed with a monthly limit, while kisspeptin is scheduled; a premix gives every part on the same days. With separate vials, a side effect can be narrowed down to one part; with a blend it cannot. [9], [48]
• Units. A blend's weight is not any part's weight, oxytocin comes in IU or mcg (1 IU is about 1.67 mcg), and blend pages say "units" without a syringe. Work out your own vial with the reconstitution calculator. [22], [19]

Common questions about the hormones and libido stack

What is in Crave?

Oxytocin 50 mg, PT-141 10 mg and kisspeptin-10 in a 5 mL vial. The supplier catalog lists 2 mg of kisspeptin-10, as does the clinic that hosts it; another clinic lists 10 mg. Without kisspeptin, the same formula is Love & Happiness. At the catalog's 25–30 units, and if a unit is 0.01 mL, one dose would hold 2.5–3 mg of oxytocin but only 500–600 mcg of PT-141. No study has tested Crave in people. [1], [16], [2]

Can you take PT-141 and oxytocin together?

People do, but the pair has never been studied. Oxytocin has no good evidence for sexual function: in the largest trial, women with sexual problems improved about as much on placebo. Both can cause flushing, and PT-141 raises blood pressure after every dose, most in the 2–4 hours after it. Sellers list the pair in opposite ratios, so how much of each you get depends on the product. How their effects add up has not been measured. [9], [20], [4], [5]

Can kisspeptin or gonadorelin replace hCG on TRT?

Not on current evidence. Both act through the pituitary, which TRT suppresses, and neither has been studied alongside TRT. In short hormone studies, testosterone blunted the pituitary's response to GnRH pulses. hCG acts on the testicles directly: in a 3-week trial in men given testosterone, it kept testosterone inside the testicles near its starting level. Some clinics switched after US compounding of hCG was restricted in March 2020. [39], [29], [30], [31]

Which is better, a blend or separate vials?

It depends on what you value. A blend means one dose but a fixed ratio and one schedule for every part. In Crave and Love & Happiness, oxytocin is five times PT-141 by weight, so reaching PT-141's labeled 1.75 mg would also deliver about 8.8 mg of oxytocin. Separate vials let you change PT-141 without changing oxytocin, and a side effect can be traced to one part. No study has compared the two. [1], [9]

Related guides

How this guide was researched

How this guide was made

This stack guide was built from the verified sources of the PT-141, oxytocin, kisspeptin, hCG and gonadorelin guides, re-citing the original documents rather than those guides. New research covered only what the combination raises: studies of the parts together, blend names and contents, and published combination schedules. Community education groups informed the descriptions of how people use the stack; no private post is quoted or linked.

The research file holds 153 records, 142 verified against the original source (122 of them through the component guides' checks); this guide cites 71. Supplier, clinic and seller pages are cited only for listed contents and published schedules, never as evidence of purity or effect.

Drafting used AI assistance under Doserly's editorial rules, followed by source checks and editorial review. It is general education, not medical advice.

Explore the sources