Heat intolerance and sweating: what to know

Sweating is one way the body releases heat. Feeling overheated sooner than other people, sweating heavily, or sweating very little can interfere with daily activity. The pattern may be influenced by fitness, body size, hormones, infection, medicines or the surrounding humidity. Heat Exhaustion is a concern when sweating is accompanied by weakness, dizziness, headache, nausea or faintness. Persistent symptoms may warrant assessment for Hyperthyroidism or other causes.

Plan outdoor activity for cooler hours, seek shade or air conditioning, wear loose breathable clothing and take regular breaks. Sip fluids before and during exertion, and replace lost salts during prolonged heavy sweating with advice from a clinician. Keep a record of triggers, sweating changes, palpitations, weight change and medicines. Avoid pushing through dizziness or nausea; cool down promptly.

Get emergency help for confusion, collapse, seizure, severe breathing difficulty, chest pain or inability to keep fluids down. Seek prompt care for fainting, very little urination, worsening weakness, a rapid or irregular heartbeat, or symptoms that do not improve after cooling. Arrange a routine review when heat intolerance is new, persistent, disrupting sleep or accompanied by unexplained weight change.

Ask whether your medicines, thyroid function, hydration, body weight or another condition could explain the pattern, and which tests or heat precautions fit your situation.