Does creatine cause muscle cramps?

Rarely, and the trials do not show it happening more often than on placebo. A 2025 analysis counted side effects across 685 human trials of creatine. Cramping or muscle pain affected 0.52 percent of 12,839 people on creatine and 0.07 percent of 13,452 on placebo, a difference with p = 0.085. That count comes from authors linked to creatine research and is not a formal meta-analysis with confidence intervals.

Myth. Creatine is not a known cause of cramps in healthy people. The International Society of Sports Nutrition, whose authors work on creatine, says well-controlled studies show creatine does not raise the incidence of muscle cramping, dehydration or injury. The trial count above points the same way. No trial in healthy athletes has made cramps its main outcome, so the answer rests on side-effect reports.

What the trials found

The signal that is not zero

The same 2025 analysis found that more creatine trials than placebo arms reported any cramping or pain at all, 20 of 685 studies (2.9 percent) against 6 of 652 (0.9 percent), with p = 0.008. The authors still concluded that cramping or pain can happen on creatine and that the incidence is low and no different from placebo. Cramps and muscle pain were lumped together, so the count cannot separate the two. Whether this is a real rare effect or a reporting habit is unresolved.

The dehydration idea did not hold up

The usual story is that creatine pulls water into muscle, leaves the rest of the body dry and causes cramps. A 2009 systematic review of 10 randomized trials in athletes tested the first half. It found no evidence that creatine hinders the body's ability to lose heat or upsets its fluid balance. Cramps themselves were not an outcome in those trials.

Football players, not randomized

Two studies followed college American football teams. Over one season in heat averaging 81 °F (27 °C), 38 players who chose to take creatine had significantly fewer cramps than 34 teammates who did not (P = .021). Across three seasons, players on about 5 g a day accounted for 39 percent of cramps, 37 of 96, in line with the 34 to 56 percent of players who used creatine. Players picked themselves, the studies were open-label, and the authors are linked to the same society. They show no excess of cramps. They cannot show that creatine prevents them.

Dialysis cramps: one small trial

In a double-blind randomized trial of 10 people on hemodialysis with frequent cramps, creatine taken before each session for 4 weeks cut cramps from 6.2 to 2.6 per 4 weeks, a 60 percent drop, and they returned to 6.6 after stopping. Serum creatinine rose from 10.7 to 12.4 mg/dl, which creatine itself produces and which is not by itself a sign of kidney damage. A 2024 systematic review of 13 trials of treatments for dialysis cramps rated this trial among the few at low risk of bias. Ten people is a very small base, and the published dose is printed in two different units across sources.

Who should be careful

Not for everyone. People with McArdle disease, a rare inherited muscle disorder. A Cochrane review of 14 trials in 364 people with muscle diseases found creatine generally well tolerated. In one McArdle trial, high-dose creatine increased muscle pain and worsened daily activities by 0.54 points on a 1 to 10 scale (0.14 to 0.93). This is the one group where a cramp-like complaint has trial evidence behind it.

People with kidney disease. The ISSN position stand notes that some have suggested people with existing kidney disease see a doctor before taking creatine, as a precaution, while finding no compelling evidence of harm to kidney function. A 2019 meta-analysis concluded creatine did not cause kidney damage at the doses and durations studied, which were short studies in healthy people.

Women. A 2020 meta-analysis of 29 studies with 951 women found no more adverse events or gastrointestinal events with creatine than without it, and no significant weight gain. Cramps were not analyzed on their own.

Where the worry came from. In a survey of 219 athletes cited by the ISSN, 90 used creatine and 27 percent of them reported cramping as a perceived side effect. Self-reports without a placebo group cannot show cause, but they are where the cramp reputation started.

What expert bodies say

The positions changed over time. A 2008 review records that an American College of Sports Medicine statement from 2000 advised people exercising hard or in the heat to avoid creatine. The review concluded that later findings show little evidence of added risk in the heat. The 2017 ISSN position stand and a 2021 ISSN review both conclude that experimental and clinical research does not support creatine causing dehydration or cramps. Both come from researchers who study creatine, and we found no newer ACSM statement on creatine and cramps.

How we searched

What would change this answer

• A randomized trial in healthy athletes with cramps as the main outcome, counted separately from muscle pain. None exists.
• A formal meta-analysis of the cramp reports in creatine trials, with confidence intervals. That would settle whether 20 studies against 6 is a rare real effect or a reporting pattern.
• Independent studies. Much of the reassurance comes from researchers linked to the creatine society and its funders.
• A larger dialysis trial with a clearly stated dose. One trial of 10 people is enough to justify the question and not enough to answer it.

More on creatine itself, including food sources and the other claims: Creatine.

Sources

1. ev-crcr-01 · Meta-analysis or systematic review · systematic pooled analysis of side effects reported in creatine clinical trials plus adverse event report databases · n = 26291
   While more studies reported GI issues (PLA 28/652 or 4.3%, Cr 63/685 or 9.2%, p < 0.001) and muscle cramping/pain (PLA 6/652 or 0.9%, Cr 20/685 or 2.9%, p = 0.008) with creatine supplementation, there were no significant differences in these side effects when the number of participants experiencing GI issues (PLA 545/13,452 or 4.2%, Cr 708/12,839 or 5.51%, p = 0.820) or muscle cramping/pain (PLA 9/13,452 or 0.07%, Cr 67/12,839 or 0.52%, p = 0.085) is evaluated in all of these studies.
   
   Who: participants of 685 human clinical trials of creatine (mostly creatine monohydrate, about 12.5 g/day for about 65 days) and 652 placebo arms
   Effect: participants with cramping/pain: creatine 67/12,839 (0.52%) vs placebo 9/13,452 (0.07%), p = 0.085; studies reporting cramping/pain: 20/685 (2.9%) vs 6/652 (0.9%), p = 0.008
   Certainty: The most direct answer. Authors from ISSN/CREAS, partly industry funding; there is no formal MA with CI. The share of studies with seizures is higher: the signal is not zero, but rare.
   J Int Soc Sports Nutr, 2025, Safety of creatine supplementation: analysis of the prevalence of reported side effects in clinical trials and adverse event reports · checked 2026-10-07 · we read the fulltext
2. ev-crcr-02 · Meta-analysis or systematic review · systematic pooled analysis of side effects reported in creatine clinical trials · n = 26291
   This means that while individuals taking creatine supplements may experience GI issues and muscle cramping/pain, the incidence is low and not different from those taking placebos.
   
   Who: participants of 685 creatine clinical trials
   Effect: incidence of GI issues and cramping/pain low and not different from placebo
   Certainty: The authors' conclusion; cramps were counted together with muscle pain, not singled out separately.
   J Int Soc Sports Nutr, 2025, Safety of creatine supplementation: analysis of the prevalence of reported side effects in clinical trials and adverse event reports · checked 2026-10-07 · we read the fulltext
3. ev-crcr-03 · Meta-analysis or systematic review · systematic review with meta-analyses of RCTs · n = 10 RCTs
   No evidence supports the concept that creatine supplementation either hinders the body's ability to dissipate heat or negatively affects the athlete's body fluid balance.
   
   Who: athletes in randomized clinical trials of creatine and thermoregulation or hydration
   Effect: no adverse effects on heat dissipation or fluid balance at recommended doses; PEDro scores 7 to 10
   Certainty: Tests the mechanism of the myth (dehydration → cramps); cramps themselves were not the endpoint.
   J Athl Train, 2009 · checked 2026-10-07 · we read the abstract
4. ev-crcr-04 · Observational data · open-label non-randomized controlled study · n = 72
   The incidence of cramping or injury in Division IA football players was significantly lower or proportional for creatine users compared with nonusers.
   
   Who: 72 NCAA Division IA football players, 38 volunteers on creatine 0.3 g/kg/day for 5 days then about 0.03 g/kg/day; mean 81 °F (27 °C), 54% humidity
   Effect: less cramping in creatine users (chi2 = 5.35, P = .021); also less heat illness or dehydration (P = .043) and fewer total injuries (P < .001)
   Certainty: Open-label, no randomization: players chose creatine themselves. Authors from ISSN. Outside the corpus; abstract from Europe PMC and E-utilities.
   J Athl Train, 2003, Cramping and Injury Incidence in Collegiate Football Players Are Reduced by Creatine Supplementation · checked 2026-10-07 · we read the abstract
5. ev-crcr-05 · Observational data · open-label non-randomized observational study · n = 3 seasons
   Creatine supplementation does not appear to increase the incidence of injury or cramping in Division IA college football players.
   
   Who: NCAA Division IA football players, 1998 to 2000 seasons, open-label creatine 15.75 g/day for 5 days then about 5 g/day
   Effect: cramping 37/96 (39%) in creatine users, proportional to a 34-56% use rate; total injuries 205/529 (39%)
   Certainty: Nonrandomized; number of players not named in the abstract. Outside the corpus; abstract from E-utilities.
   Mol Cell Biochem, 2003, Creatine supplementation during college football training does not increase the incidence of cramping or injury · checked 2026-10-07 · we read the abstract
6. ev-crcr-06 · Randomized controlled trial(s) · randomized double-blind placebo-controlled trial · n = 10
   The frequency of symptomatic muscle cramps decreased by 60% in the creatine monohydrate treatment group (6.2+/-0.8 vs 2.6+/-1.8 times/4 weeks, P<0.05) during the treatment period.
   
   Who: 10 hemodialysis patients with frequent muscle cramps; creatine monohydrate or placebo before each session for 4 weeks
   Effect: cramps 6.2 ± 0.8 vs 2.6 ± 1.8 times per 4 weeks (P < 0.05); back to 6.6 ± 1.1 in washout; serum creatinine rose from 10.7 to 12.4 mg/dl
   Certainty: A tiny RCT. The abstract says "12 mg"; in the ISSN 2021 PMC review the dose is 12 g; the unit is in question. Creatinine rises because of creatine itself, not a sign of kidney damage. Outside the corpus.
   Nephrol Dial Transplant, 2002, Creatine monohydrate treatment alleviates muscle cramps associated with haemodialysis · checked 2026-10-07 · we read the abstract
7. ev-crcr-07 · Randomized controlled trial(s) · systematic review of experimental studies, RoB2 · n = 13 studies
   The studies testing L-carnitine and creatine monohydrate were the only ones deemed to have a low risk of bias.
   
   Who: patients on dialysis with muscle cramps in experimental studies of 9 interventions
   Effect: creatine monohydrate and L-carnitine trials the only ones at low risk of bias; vitamins C and E most studied with positive results
   Certainty: No pooling; about creatine: one RCT (ev-crcr-06).
   Semin Dial, 2024 · checked 2026-10-07 · we read the abstract
8. ev-crcr-08 · Meta-analysis or systematic review · Cochrane systematic review and meta-analysis of RCTs · n = 364
   One trial reported a significant deterioration of activities of daily living (mean difference 0.54 on a 1 to 10 scale; 95% CI 0.14 to 0.93) and an increase in muscle pain during high-dose creatine treatment in McArdle disease.
   
   Who: 364 participants with muscular dystrophies, inflammatory myopathies or metabolic myopathies
   Effect: no clinically relevant adverse events in dystrophies; in McArdle disease worse activities of daily living (MD 0.54 on a 1-10 scale, 95% CI 0.14 to 0.93) and more muscle pain at high dose
   Certainty: Main group for caution regarding muscle pain: McArdle disease (glycogenosis V).
   Cochrane Database Syst Rev, 2013 · checked 2026-10-07 · we read the abstract
9. ev-crcr-09 · Meta-analysis or systematic review · systematic review and meta-analysis · n = 951
   There were no significant differences in total adverse events, (risk ratio (RR) 1.24 (95% CI 0.51, 2.98)), gastrointestinal events, (RR 1.09 (95% CI 0.53, 2.24)), or weight gain, (mean difference (MD) 1.24 kg pre-intervention, (95% CI -0.34, 2.82)) to 1.37 kg post-intervention (95% CI -0.50, 3.23)), in CrM supplemented females, when stratified by dosing regimen and subject to meta-analysis.
   
   Who: female participants in creatine monohydrate studies that monitored adverse outcomes
   Effect: total adverse events RR 1.24 (95% CI 0.51 to 2.98); gastrointestinal events RR 1.09 (0.53 to 2.24); no serious adverse outcomes
   Certainty: Seizures were not analyzed separately; overall safety picture in women.
   Nutrients, 2020 · checked 2026-10-07 · we read the abstract
10. ev-crcr-10 · Meta-analysis or systematic review · systematic review and meta-analysis · n = 15 studies
    The findings indicate that creatine supplementation does not induce renal damage in the studied amounts and durations.
    
    Who: participants of creatine supplementation studies with renal outcomes; 15 studies reviewed, 6 pooled
    Effect: no renal damage at studied amounts and durations
    Certainty: Short studies in healthy people; kidney patients are outside the conclusion.
    J Ren Nutr, 2019 · checked 2026-10-07 · we read the abstract
11. ev-crcr-11 · Position of an expert body · position stand of a professional society · n = —
    Unsubstantiated anecdotal claims described in the popular media as well as rare case reports described in the literature without rigorous, systematic causality assessments have been refuted in numerous well-controlled clinical studies showing that creatine supplementation does not increase the incidence of musculoskeletal injuries [22, 111, 112, 241], dehydration [111, 112, 117, 122, 127–129, 242], muscle cramping [76, 106, 111, 112, 117], or gastrointestinal upset [22, 111, 112, 241].
    
    Who: healthy and clinical populations taking creatine at recommended doses
    Effect: no increase in musculoskeletal injuries, dehydration, muscle cramping or GI upset in controlled studies
    Certainty: ISSN position; the author group is linked to creatine research.
    J Int Soc Sports Nutr, 2017, International Society of Sports Nutrition position stand: safety and efficacy of creatine supplementation in exercise, sport, and medicine · checked 2026-10-07 · we read the fulltext
12. ev-crcr-12 · Position of an expert body · position stand of a professional society · n = —
    While some have suggested that individuals with pre-existing renal disease consult with their physician prior to creatine supplementation in an abundance of caution, these studies and others have led researchers to conclude that there is no compelling evidence that creatine supplementation negatively affects renal function in healthy or clinical populations [5, 6, 22, 53, 259, 266, 267].
    
    Who: individuals with pre-existing renal disease
    Effect: precautionary physician consultation; no compelling evidence of harm to renal function
    Certainty: Caution for caution's sake, but this is the only direct "ask the doctor" group.
    J Int Soc Sports Nutr, 2017, International Society of Sports Nutrition position stand: safety and efficacy of creatine supplementation in exercise, sport, and medicine · checked 2026-10-07 · we read the fulltext
13. ev-crcr-13 · Position of an expert body · expert narrative review · n = 219
    For example, in a survey involving 219 athletes, 90 participants reported using creatine with 34 of them (38%) reporting perceived negative effects such as cramping (27%) [77].
    
    Who: survey of 219 athletes, 90 creatine users; NCAA baseball and football players using creatine
    Effect: 38% of the 90 creatine users reported perceived negative effects; cramping 27%; self-report, no placebo group
    Certainty: Where the myth comes from: a self-reported survey, no dose control. Exceeding the dose in 91% is a practical tip.
    J Int Soc Sports Nutr, 2021, Common questions and misconceptions about creatine supplementation: what does the scientific evidence really show? · checked 2026-10-07 · we read the fulltext
14. ev-crcr-14 · Position of an expert body · expert narrative review · n = —
    In summary, experimental and clinical research does not validate the notion that creatine supplementation causes dehydration and muscle cramping.
    
    Who: athletes and patients in experimental and clinical studies
    Effect: no support for creatine causing dehydration or muscle cramping
    Certainty: A review-type conclusion; based on the same Greenwood and Chang.
    J Int Soc Sports Nutr, 2021, Common questions and misconceptions about creatine supplementation: what does the scientific evidence really show? · checked 2026-10-07 · we read the fulltext
15. ev-crcr-15 · Position of an expert body · narrative review · n = —
    Considering these new published findings, little evidence exists that creatine supplementation in the heat presents additional risk, and this should be taken into consideration as position statements and other related documents are published.
    
    Who: athletes exercising in hot environments or managing weight
    Effect: ACSM 2000 advised avoiding creatine; later trials suggest no added risk in the heat
    Certainty: Discrepancy of positions: ACSM 2000 versus ISSN 2017. A newer ACSM position specifically on creatine and cramps was not found. Outside the corpus; abstract from E-utilities.
    Br J Sports Med, 2008, Putting to rest the myth of creatine supplementation leading to muscle cramps and dehydration · checked 2026-10-07 · we read the abstract