Heat cramps symptoms: what to notice

A heat cramp can make a muscle feel hard, knotted or difficult to move. The spasm may come on during activity or after you stop. Calves, thighs, shoulders, arms and the abdominal wall can be affected. [Muscle Cramps](/symptoms/muscle-cramps/) describes the tightening, while [Muscle Aches](/symptoms/muscle-aches/) is usually a broader soreness rather than a sudden spasm.

Thirst, fatigue, headache and reduced urination may occur when sweating has exceeded fluid intake. This pattern can accompany [Dehydration](/conditions/dehydration/), but symptoms can overlap with other problems, so context matters.

Stop exercising or working, sit in a cool place and remove extra layers. Gently stretch the affected muscle without bouncing. Take small, frequent sips of water; after prolonged heavy sweating, ask a pharmacist or clinician whether [Oral Rehydration Therapy](/treatments/acute-and-urgent-care/oral-rehydration-therapy/) is suitable.

Do not return to heat or strenuous activity while cramping, dizzy or weak. Keep track of whether symptoms improve with cooling and fluids, and avoid salt tablets unless prescribed or specifically recommended.

Get urgent help for confusion, fainting, seizures, severe weakness, breathing difficulty, chest pain, repeated vomiting or an inability to drink. Also seek care if spasms persist despite cooling and rest, because a more serious heat illness or another cause may need assessment.

Ask whether your symptoms fit heat cramps, how to replace fluids safely, and when you may return to activity. Tell the clinician about the temperature, your exertion, sweating, medicines and any vomiting or diarrhoea.