What should you know about calf cramps and dehydration?

Sweat, vomiting, diarrhoea, fever, or poor intake can reduce body water. This may cause thirst, dry mouth, darker urine, constipation, dizziness, and muscle cramps. A calf cramp is a common presentation of dehydration, but it can also occur for other reasons. Gastroenteritis and heat exhaustion are possible settings for fluid loss; kidney stones or a urinary tract infection may cause urinary symptoms but do not explain every cramp.

Rest in a cool place and sip fluids regularly. If you have lost fluid through vomiting or diarrhoea, ask a pharmacist or clinician whether an oral rehydration drink is suitable. Stretch the calf gently when it tightens. Avoid strenuous activity and alcohol until you feel recovered. People with kidney, heart, or fluid-balance problems should seek tailored advice before increasing fluids.

Seek urgent help for confusion, fainting, inability to keep fluids down, severe weakness, very little urine, rapid breathing, or collapse. Get prompt assessment for calf swelling, warmth, redness, severe pain, or breathlessness. Arrange review when cramps continue after rehydration or fluid loss keeps recurring.

Ask how much fluid is appropriate for you, whether electrolytes or kidney function need checking, and how to manage rehydration during future illness or heat exposure.