# Kisspeptin

Top-of-axis GnRH stimulator for libido/testosterone; chronic use can crash the axis.

- Page: https://peprank.xyz/peptides/kisspeptin
- Category: Hormones & libido (Research peptide)
- Also known as: kisspeptin-10; KP-10; metastin; kisspeptin-54
- Routes: Nasal / Injection
- Sequence: YNWNSFGLRF (kisspeptin-10, C-amide; full kisspeptin-54 is the C-terminal 54 aa of KISS1)
- Safety tier: Strict: Avoid · Balanced: Caution · Evidence only: Caution
- Risk axes (0 none to 3 severe): Seen harm 0, Mechanism 2, Data gap 2, Silent harm 2, Product 3
- Positive: 52% of 30 graded reports glowing or positive, shrunk toward the 49% all-report average by 8 reports' weight
- Rank: #32 of 61 research peptides
- Graded reports: 30 (Glowing 6, Positive 10, Mixed 2, Nothing 10, Negative 2)
- Evidence: Small human studies — Acute physiology studies; reproductive medicine trials
- Access: Grey market
- Onset: Libido effects in responders within 1-3 doses (hours to a few days); some report needing weeks. LH peaks 30-60 minutes after a kisspeptin-10 dose.
- Lasts: Kisspeptin-10 is cleared in minutes and its LH pulse lasts 1-3 hours, yet users describe libido effects lasting 1-3 days per injection. Daily high doses blunt the response.
- Cost per month: ≈ €4.1–12 (at 29–86 mcg/day, XL Peptides at €4.78/mg, trust-3 shop)
- Dose users report: 86–170 mcg/day (median 88 mcg, n=6)
- Updated: 2026-10-30

**Why Avoid under the strict bar:** Directly manipulates the HPG axis; continuous or long-acting exposure suppresses it.

## What users report

There are surprising libido wins in women (perimenopausal and already on HRT, one with periods and ovulation back after pelvic radiation) and in men with post-SSRI sexual dysfunction (PSSD), a few claiming full recovery. Others feel 'more chill' with no libido change, and testosterone gains are small, absent, or reversed on labs after weeks of use. Knowledgeable commenters stress it only helps if the bottleneck is hypothalamic. About a third report nothing; daily 150-250 mcg users mention insomnia and a rise in oestradiol.

**Effects:** libido restoration (esp. women); LH/testosterone pulses; cycle regulation

**Downsides:** very short action (1-3 h); period shifts; inconsistent effect

**Risks:** Hormonal axis: sustained exposure desensitises the receptor and drives testosterone into castration range (TAK-448 trials); FDA category 2 (immunogenicity, no safety data for proposed routes)

**Typical use:** 100-200 mcg 2-3x/week, or kisspeptin-10 pre-activity.

**Getting it:** Research-peptide vendors sell kisspeptin-10 as 5-10 mg vials and some nasal sprays; a few US TRT clinics compounded it as an hCG substitute before FDA placed it in Category 2. Kisspeptin-54, the form used in most trials, is only available in UK research settings.

**Stacked with:** PT-141 (Combined for libido; users call kisspeptin slower and gentler, PT-141 stronger but nausea-prone.); Enclomiphene (Men trying to raise testosterone without TRT pair them, kisspeptin driving LH while enclomiphene blocks oestrogen feedback; results on labs are mixed.); TRT / hCG (Used on TRT in place of hCG to keep testicular size; one user saw no sperm recovery on it where hCG worked within a week.)

## Risk profile

- **Seen harm 0/3:** Acute studies in volunteers and IVF trials in the low hundreds report no serious adverse events and no blood-pressure or heart-rate change, but no study has looked at the repeated self-dosing people practise.
- **Mechanism 2/3:** Hormone-axis manipulation: single doses raise LH and testosterone, but sustained exposure to the analogue TAK-448 drove testosterone below castration levels by day 8.
- **Data gap 2/3:** Only acute physiology studies and small IVF trials (the largest 60 women); FDA found no or limited safety data for the routes proposed.
- **Silent harm 2/3:** Axis suppression builds up over days of frequent dosing and shows on LH and testosterone tests, though libido changes may be noticed.
- **Product 3/3:** Grey-market subcutaneous vials, with some nasal sprays.
- **Never if:** Hormone-sensitive cancers; Trying to conceive, outside a fertility clinic; Pregnancy or breastfeeding (no human reproductive data)

## Top reports

- Glowing, libido-hormones, 0.5-2 mcg up to 3x/day, 5 days on / 2 off: “sex drive is good, ed is all but gone, sperm count upper normal.” — [r/PSSD](https://www.reddit.com/r/PSSD/comments/1euo794/i_have_recovered_for_over_a_year_with/lilpw95/)
- Glowing, libido-hormones: “After about a week, I had improved. In a month, I had returned to the way I was iny 20's and 30's. Not only can I achieve orgasm, I can come more easily than ever... and I'm not young.” — [r/PSSD](https://www.reddit.com/r/PSSD/comments/1rggymx/peptides_kisspeptin_anyone_tried_it/ocmatbb/)
- Glowing, libido-hormones, 200 mcg/day fasted, mornings: “M(57) I'm taking 200 mcg a day fasted in the morning. I'm getting morning wood, sex dreams, and random erections. It's like being 16 again.” — [r/PSSD](https://www.reddit.com/r/PSSD/comments/1rggymx/peptides_kisspeptin_anyone_tried_it/ou0le3g/)
- Glowing, libido-hormones, 1 mg/day: “I'm a 45yo woman. It worked to bring my libido back. I was repulsed by the thought of sex. Even after starting hrt.” — [r/BodyHackGuide](https://www.reddit.com/r/BodyHackGuide/comments/1vml33t/kisspeptin_how_come_no_one_tries_it/p3joarr/)
- Glowing, libido-hormones, 200 mcg 2-3x/week: “I didn't have periods prior due to a previous cancer and radiation in the pelvic area. Now my periods are stable and I ovulate. I did have no libido prior, and I was drier than a desert. Now that is solved as well.” — [r/BodyHackGuide](https://www.reddit.com/r/BodyHackGuide/comments/1vml33t/kisspeptin_how_come_no_one_tries_it/p6dk5vn/)

## Cheapest in Europe

- [Baltic Peptides](https://balticpeptides.com/product/kisspeptin-10/) (LT): Kisspeptin-10 10mg vial, €35, €3.50/mg
- [Baltic Peptides](https://balticpeptides.com/product/kisspeptin-10/) (LT): Kisspeptin-10 10mg nasal spray, €40, €4.00/mg (contents not stated on the page)
- [XL Peptides](https://xlpeptides.com/product/kisspeptin-10-5mg/) (GB): Kisspeptin-10 5mg Research Peptide, €24, €4.78/mg
- [Semax Polska](https://semaxpolska.com/en/kisspeptin-10-5mg/) (PL): Kisspeptin-10 5 mg + bacteriostatic water 3 ml, €30, €6.05/mg
- [Europa-Peptide](https://europa-peptide.de/en/shop/kisspeptin-5mg/) (PL): Kisspeptin 5mg, €39, €7.78/mg

## Studies

- [George et al. 2011: kisspeptin-10 is a potent stimulator of LH and increases pulse frequency in men](https://pmc.ncbi.nlm.nih.gov/articles/PMC3380939/) (open-label, 2011): IV kisspeptin-10 raised LH within 30 minutes, maximally at 1 mcg/kg, with a smaller response at 3 mcg/kg; a 22.5 h infusion raised LH pulse frequency and testosterone in healthy men.
- [Comninos et al. 2017: kisspeptin modulates sexual and emotional brain processing in humans](https://pmc.ncbi.nlm.nih.gov/articles/PMC5272173/) (rct, n=29, 2017): A kisspeptin-54 infusion enhanced limbic brain activity to sexual and couple-bonding images in healthy men and reduced reported sexual aversion, versus placebo.
- [Thurston et al. 2022: kisspeptin administration in women with hypoactive sexual desire disorder](https://pubmed.ncbi.nlm.nih.gov/36287566/) (rct, n=32, 2022): A single kisspeptin infusion modulated sexual and facial-attraction brain processing in premenopausal women with HSDD versus placebo; it was well tolerated.
- [Mills et al. 2023: kisspeptin, sexual brain processing and penile tumescence in men with HSDD](https://pubmed.ncbi.nlm.nih.gov/36735255/) (rct, n=32, 2023): A kisspeptin infusion activated the sexual-processing network, increased penile tumescence to erotic video and raised 'happiness about sex' versus placebo in men with low desire.
- [Jayasena et al. 2014: kisspeptin-54 triggers egg maturation in women undergoing IVF](https://pmc.ncbi.nlm.nih.gov/articles/PMC4109525/) (open-label, n=53, 2014): One subcutaneous kisspeptin-54 injection induced an LH surge and egg maturation at every dose tested; 12 of 53 women had a clinical pregnancy.
- [MacLean et al. 2014: sustained exposure to the kisspeptin analogue TAK-448 down-regulates testosterone into the castration range](https://doi.org/10.1210/jc.2013-4236) (controlled, 2014): Single doses raised LH and testosterone, but continuous dosing in healthy men and prostate-cancer patients drove testosterone into the castration range, showing the axis shuts down under sustained stimulation.

## Sources

- [Sustained exposure to kisspeptin analogue TAK-448 down-regulates testosterone into castration range (JCEM 2014)](https://doi.org/10.1210/jc.2013-4236)
- [Kisspeptin-10 is a potent stimulator of LH in men (JCEM 2011)](https://doi.org/10.1210/jc.2011-0089)
- [FDA category 2 note on kisspeptin-10](https://www.fda.gov/drugs/human-drug-compounding/certain-bulk-drug-substances-use-compounding-may-present-significant-safety-risks)