Primary vs Secondary Hyperhidrosis
| Type | Features |
|---|---|
| Primary (focal) | Specific body areas (underarms, hands, feet), onset usually in childhood/adolescence, no other symptoms, often family history |
| Secondary (generalised) | Whole body sweating, adult onset, associated with an underlying condition or medication |
Causes of Secondary Hyperhidrosis
- Hyperthyroidism (overactive thyroid)
- Menopause (hot flushes and night sweats)
- Diabetes (especially with hypoglycaemia episodes)
- Anxiety disorders
- Infections (TB, HIV — especially with night sweats)
- Certain medications (antidepressants, some blood pressure medications)
- Rarely: certain cancers (lymphoma)
Blood Tests to Investigate Secondary Causes
| Test | Rules Out |
|---|---|
| TSH / T4 | Hyperthyroidism |
| Fasting glucose / HbA1c | Diabetes |
| FBC + ESR | Infection, lymphoma |
| FSH/LH | Menopause |
Treatment Options for Primary Hyperhidrosis
| Treatment | Effectiveness |
|---|---|
| Aluminium chloride antiperspirants (prescription strength) | First-line — effective for many, applied at night |
| Botox injections | Highly effective, lasts 4-6 months, especially for underarms |
| Iontophoresis | Effective for palms/soles — mild electrical current through water |
| Oral medications (glycopyrronium) | For more widespread sweating |
| Surgery (sympathectomy) | Last resort — risk of compensatory sweating elsewhere |
Night Sweats Deserve Extra AttentionDrenching night sweats (requiring a change of nightclothes/sheets) combined with weight loss or fever should always be investigated, as they can (rarely) signal serious underlying conditions like lymphoma or tuberculosis.
Is excessive sweating just anxiety?
Not usually — most focal hyperhidrosis is a primary condition unrelated to anxiety, though anxiety can worsen episodes. It shouldn't be dismissed as 'just nerves' without appropriate assessment.
Does Botox for sweating hurt?
Botox for hyperhidrosis is typically very well tolerated; local anaesthetic cream or ice can be used before injections for comfort.
Can diet affect sweating?
Spicy foods, caffeine, and alcohol can trigger or worsen sweating in susceptible people, though eliminating them rarely resolves primary hyperhidrosis completely.
Medical Disclaimer: This page is for general education only and does not replace professional medical advice. Always consult a qualified healthcare provider.