Creatine pulls water into muscle cells, one reason muscles look fuller on it. The old myths say this automatically causes dehydration and cramping, but controlled studies in athletes training in heat show no extra dehydration and, in some cases, fewer cramps and heat illnesses compared to placebo.
The real risk is more indirect: people take creatine, train harder, sweat more, add caffeine-heavy pre-workouts, and forget to raise water and electrolyte intake. In hot climates, that combination can tip someone toward headaches, dizziness, darker urine, and higher heart rate-and creatine becomes an easy scapegoat instead of the overall hydration strategy.