Drug-Induced Hyperhidrosis: An Evidence Overview by Class

Medicines are a leading cause of secondary sweating

When sweating has an identifiable external cause, medicines are near the top of the list. Dermatology references describe drug-induced hyperhidrosis as one of the most common causes of secondary (non-familial) hyperhidrosis. The effect crosses many therapeutic areas (psychiatry, pain, neurology, endocrinology) because the drugs act at different points on a single pathway that ends at the sweat gland.

That shared endpoint is acetylcholine, the main chemical messenger at eccrine sweat glands. Some drugs raise cholinergic tone directly; others act higher up, on the brain's thermoregulatory centre or on serotonin and adrenaline signalling. The result is the same: sweating in excess of what the body needs to stay cool.

The table summarizes the drug classes commonly implicated, the proposed mechanism, and whether a reliable frequency figure exists. Where solid incidence numbers are available, they live on dedicated companion pages; where they are not, the class is still recognized qualitatively.

Antidepressants: the best-quantified class

Antidepressants are where the numbers are firmest, because sweating is reported directly on FDA prescribing labels. Across SSRIs and SNRIs, reported sweating runs roughly 5% to 21%, with the serotonin–noradrenaline reuptake inhibitors (SNRIs) at the higher end and a clear dose relationship for at least one drug. Because each figure comes from a different trial, the percentages describe individual drugs rather than a head-to-head ranking.

We keep the full drug-by-drug label figures on a separate page so this overview stays at the class level; see the companion page on antidepressants and sweating for the detail.

Opioids and cholinergic drugs

Opioids are the other class with a memorable figure: excessive sweating has been reported in up to about 45% of methadone-maintenance patients, and sweating is described across the opioid class in pain and palliative care. The proposed mechanisms are histamine release and a central effect on the body's temperature set-point.

Cholinesterase inhibitors act more directly. By blocking the breakdown of acetylcholine, the very transmitter that switches sweat glands on, drugs such as donepezil and rivastigmine (used in dementia) and pyridostigmine (used in myasthenia gravis) can increase sweating as a predictable, on-target effect. Tricyclic antidepressants are also recognized causes, though their labels typically list increased perspiration without a percentage.

What real-world reporting shows

National drug-safety monitoring backs up the class picture. New Zealand's medicines regulator counted 376 reports of hyperhidrosis linked to medicines (excluding vaccines) between January 2010 and September 2024, with the SNRI venlafaxine the single most frequently reported drug at 49 reports. Spontaneous-reporting counts like these cannot measure how often sweating actually happens (they reflect what clinicians and patients chose to report) but they confirm which drugs generate the most real-world signal.

Endocrine and metabolic drugs round out the picture. Thyroid hormone taken in excess, systemic corticosteroids, and hormone-modifying agents can drive sweating through vasomotor effects, while insulin and sulfonylureas cause sweating as one of the body's warning signs of low blood sugar rather than as a direct glandular effect.

How to read a drug's sweating risk

A few principles help. First, sweating is a genuine, recognized effect of many common medicines, so a new onset of sweats after starting or increasing a drug is worth noting. Second, the presence of "hyperhidrosis," "sweating" or "increased perspiration" on a label tells you the effect is recognized, but the absence of a percentage does not mean the effect is rare; many labels simply do not quantify it. Third, real incidence figures exist mainly for antidepressants and methadone; for most other drugs the evidence is qualitative.

Sweating that is new, heavy, one-sided, or paired with fever, weight loss or night sweats deserves a clinical review rather than being assumed to be a drug effect. Whether a medicine is the cause (and what, if anything, to do about it) is a conversation for the prescribing clinician, not a reason to stop treatment on your own.

Methodology and limitations

This overview is anchored on a peer-reviewed pharmacology review of drug effects on sweating (Cheshire & Fealey 2008), a government pharmacovigilance article (New Zealand Medsafe 2024), and a dermatology reference (DermNet), with class-level incidence figures drawn from FDA labels (summarized on our antidepressants page) and a methadone survey (Al-Adwani & Basu 2004). Each figure was traced to its source.

Limitations: robust incidence figures exist for only a minority of these drugs: chiefly antidepressants (FDA labels) and methadone. For other classes the association is recognized but not well quantified, so the table mixes percentages with qualitative labels rather than implying they are comparable. Spontaneous-report counts (e.g., the New Zealand figures) reflect reporting behaviour, not true frequency. Drug labels use varying terms and different placebo comparators. A drug being associated with sweating does not establish that it is the cause in any individual. This page is general education, not medical advice, and not a basis for starting, stopping or changing medication.

Frequently asked questions

Which drugs most commonly cause excessive sweating?

The best-recognized classes are cholinesterase inhibitors, SSRIs and SNRIs, opioids, and tricyclic antidepressants (Cheshire & Fealey 2008). Antidepressants have the firmest numbers (about 5–21% on FDA labels), and methadone stands out among opioids (up to ~45% in one survey).

How do medicines cause sweating?

Most act on a single pathway that ends at the sweat gland, where acetylcholine is the main messenger. Some drugs raise acetylcholine directly (cholinesterase inhibitors); others act on the brain's temperature centre or on serotonin and adrenaline signalling (antidepressants, opioids).

Is drug-induced sweating common?

It is one of the more common causes of secondary (non-familial) sweating. National reporting supports this (New Zealand recorded 376 medicine-linked hyperhidrosis reports over about 15 years), though such counts reflect reporting, not true incidence.

My label doesn't list a sweating percentage. Does that mean it's rare?

Not necessarily. Many labels list sweating or 'increased perspiration' without a figure. The absence of a number reflects how the effect was reported in trials, not proof that it is uncommon.

Should I stop a medicine that makes me sweat?

No, not on your own. Sweating that is new, severe, or accompanied by fever, weight loss or night sweats should be reviewed by a clinician, who can weigh whether the drug is the cause and what options exist. Medication decisions belong with a prescriber.

Sources

Primary peer-reviewed studies and official sources first, then reviews and institutional framing (secondary).

1. Cheshire WP, Fealey RD. Drug-induced hyperhidrosis and hypohidrosis: incidence, prevention and management. Drug Saf. 2008;31(2):109–126. Identifies cholinesterase inhibitors, SSRIs, opioids and tricyclic antidepressants as causes of hyperhidrosis. PubMed
2. New Zealand Medicines and Medical Devices Safety Authority (Medsafe). Medicines that make you sweat: drug-induced hyperhidrosis. Prescriber Update, December 2024. 376 medicine-linked hyperhidrosis reports (2010–Sep 2024); venlafaxine most frequent (49). Medsafe (govt)
3. Al-Adwani A, Basu N. Methadone and excessive sweating. Addiction. 2004;99(2):259. Up to ~45% of methadone-maintenance patients. Journal (Addiction)
4. US Food and Drug Administration / DailyMed. Prescribing information (adverse reactions) for SSRI and SNRI antidepressants. DailyMed, National Library of Medicine. Label sweating incidence summarized on our antidepressants page. DailyMed
5. DermNet. Drug-induced hyperhidrosis. DermNet. Describes drug-induced hyperhidrosis as a common cause of secondary hyperhidrosis and lists implicated classes. (secondary) DermNet

How to cite this page

Related reading on this site

• Antidepressants and sweating: incidence by drug class
• Opioid-induced sweating: what the research shows
• Excessive sweating: the topic hub
• What can trigger sweating?
• Preparing for a doctor visit about sweating