"Does creatine affect libido" is searched as if somebody had measured it. Nobody has. Read every creatine trial indexed in PubMed and none reports sex drive, erections or sexual satisfaction as an outcome. What exists instead is a hormone literature that is often cited for the question, one fifteen-man sperm pilot, a handful of FDA reports, and three studies registered in the last year that have added a sexual-function questionnaire and not yet reported.
This page lays out each of those, dated, so the gap is visible.
The census
| Where we looked (2026-11-02) | Query | What came back |
|---|---|---|
| PubMed | creatine + supplement or monohydrate + libido / sexual function / sexual desire / erectile / sexual dysfunction | 2 records, neither a creatine trial (a review of L-arginine, an American Heart Association statement on statins) |
| PubMed | creatine + supplement + sperm / semen / fertility, human studies | 12 records, 1 controlled creatine trial (Nedeljkovic 2026, below) |
| ClinicalTrials.gov | intervention creatine, outcome text sexual / erectile / libido / IIEF | 9 studies matched; 3 actually measure sexual function, none with results |
| FDA CAERS (openFDA) | products with "creatine" in the brand name | 210 reports, 6 naming a sexual or reproductive reaction |
So the answer to "what do trials show" is not "no effect". It is "no data". Those are different findings, and the second is the one the evidence supports.
The three studies that will measure it
ClinicalTrials.gov's outcome search returned nine creatine studies on 2 November 2026. Reading each record's outcome measures, six use the matched word for something else. Three genuinely include sexual function:
| Study | Design | How sexual function is measured | Status |
|---|---|---|---|
| NCT07451496 (PROMETHEUS) | Ageing trial combining lifestyle, supplements and drugs; creatine is one of several interventions | Brief Sexual Function Inventory (men), Female Sexual Function Index (women) | Recruiting, start 2025-09 |
| NCT07580846 (ATENEA) | Observational: adherence to creatine-based supplementation in oestrogen-depleted women | A menopause quality-of-life questionnaire with a sexuality domain | Recruiting, start 2026-03 |
| NCT07827014 | Open-label two-arm pilot of a creatine product | "Sexual dysfunction" rated 1–5 among eight side-effect items | Recruiting, start 2026-10 |
None is a placebo-controlled test of creatine alone on sex drive. The first mixes creatine into a bundle of interventions, so a result could not be pinned on creatine; the second has no control arm; the third tracks sexual dysfunction as a possible side effect, not as a benefit. When any of them posts results it will be the first sexual-function data on creatine in people, and it will still not answer the question cleanly.
Why the question gets asked: testosterone and DHT
Most claims that creatine raises libido run through testosterone. Four randomised trials have measured testosterone during creatine use, and this site's creatine and testosterone page reads each one. In short: testosterone was unchanged in two, fell in both arms of a training-overreach trial, and in the twelve-week trial it rose more on placebo (216 ng/dL) than on creatine (124 ng/dL), with no interaction between supplement and time.
The one hormonal change on record is in dihydrotestosterone. In the 2009 trial of 20 college rugby players, DHT rose 56% after seven days of 25 g a day and stayed 40% above baseline after two weeks of 5 g a day, while testosterone did not move (PMID 19741313). The later twelve-week trial that measured DHT found no group-by-time interaction for it (PMID 40265319). Neither trial asked participants anything about desire or sexual function. A hormone moving in a blood test is not a measurement of libido, and in this case the hormone that moved did not replicate.
The sperm pilot
The one controlled study of creatine and semen was published in 2026 by a Serbian group that has run many creatine trials (Nedeljkovic 2026, PMID 41052075). Fifteen men aged about 25, five of them with low sperm counts, were randomised to creatine, creatine with ubiquinol, or a control for eight weeks.
- Average sperm concentration: a non-significant trend upward in the creatine-plus-ubiquinol arm, +7.4 million per millilitre (p = 0.22).
- Responders: 6 of 10 men in the two creatine arms improved on concentration, against 1 of 5 controls (p ≤ 0.05).
- Low-count men: all who received creatine improved on concentration; controls stayed the same or fell.
The authors describe it as an exploratory pilot. Fifteen men split three ways leaves five per arm; a responder count in arms that small moves with a single person. It says nothing about libido or erections, which it did not measure. Fertility questions belong with a clinician.
What the FDA's reports contain
The FDA's adverse-event database for foods and supplements (CAERS) records what people and clinicians report after using a product. On 2 November 2026, openFDA held 210 reports naming a product with "creatine" in its brand name. Six list a sexual or reproductive reaction:
| Reaction named | Reports | Creatine product the only suspect | Other products also suspected |
|---|---|---|---|
| Erectile dysfunction | 2 | 0 | 2 (one with a testosterone booster, one with an L-arginine "hyperemia" product and caffeine pills) |
| Decreased libido | 1 | 1 (2026) | 0 |
| Gynaecomastia with testicular atrophy | 2 | 2 (2013, 2016) | 0 |
| Testicular pain | 1 | 0 | 1 (creatine listed as concomitant, not suspect) |
Read plainly: three reports in roughly twenty years name a creatine product alone alongside a sexual or reproductive reaction; the two erectile-dysfunction reports both involve products sold on testosterone or blood-flow claims. The FDA's own guidance on CAERS is that a report does not establish cause and reports are neither complete nor verified. The counts can show that people have linked these symptoms to creatine products. They cannot give a rate, and they cannot separate creatine from the other ingredients in a multi-ingredient product. Brand names from the reports are not printed here.
What is not established
- Whether creatine changes sex drive, in either direction. No trial has measured it.
- Whether creatine affects erectile function. No trial has measured it; the two FDA reports both involve other suspect products.
- Whether the 2009 DHT rise has any sexual consequence. It was not measured then and has not replicated since.
- Whether creatine affects male fertility. One fifteen-man pilot; nothing larger.
- Anything about women. The only study that will report sexual function in women (ATENEA) is observational and has not reported.
Who should talk to a clinician
Anyone noticing a change in libido or erections, whatever they are taking. Erectile dysfunction in particular can be an early sign of vascular disease, and a supplement should not be assumed to be the cause, or ruled out, without an examination. Anyone with a fertility question, or anyone on hormone therapy, has a question for a doctor rather than for the creatine literature, which at present has nothing to say. Several creatine labels already say as much — the 1st Phorm warning list, for one, names prescription medicines and several conditions.
Related reading: is creatine a steroid?, creatine side effects, creatine hair loss and the creatine hub.
Sources and dates
- PubMed E-utilities searches, run 2026-11-02: creatine + supplement/monohydrate + libido OR "sexual function" OR erectile OR "sexual desire" OR "sexual dysfunction" (2 records); creatine + supplement + sperm OR semen OR fertility, humans (12 records).
- ClinicalTrials.gov API v2, intervention "creatine" with outcome text sexual / erectile / libido / IIEF, 9 records, each record's outcome measures read on 2026-11-02: NCT07451496, NCT07580846, NCT07827014.
- Nedeljkovic D et al. Creatine with and without ubiquinol and sperm quality, randomised pilot. Nutr Health 2026;32(5):1575–82. PMID 41052075, abstract read 2026-11-02.
- van der Merwe J, Brooks NE, Myburgh KH. Clin J Sport Med 2009;19(5):399–404. PMID 19741313.
- Lak M et al. Does creatine cause hair loss? A 12-week randomized controlled trial. J Int Soc Sports Nutr 2025;22(sup1):2495229. PMID 40265319.
- FDA CAERS via the openFDA food/event endpoint,
products.name_brand:creatine, all 210 reports downloaded 2026-11-02; the six with a sexual or reproductive reaction read for products and their roles.