Cholinesterase Inhibitors and Sweating

Why cholinesterase inhibitors cause sweating

Eccrine sweat glands are switched on by acetylcholine released from sympathetic cholinergic fibres. Under normal conditions the enzyme acetylcholinesterase quickly breaks acetylcholine down at the synapse. Cholinesterase inhibitors slow that breakdown, leaving more acetylcholine available to bind muscarinic receptors on sweat glands. The result is a predictable, dose-related increase in sweating, one of the classic "muscarinic" effects of this drug class alongside salivation, lacrimation, and gastrointestinal cramping.

Because sweating is an on-target pharmacological effect rather than an idiosyncratic reaction, it is one of the more consistent side effects of the class. Standard pharmacology reviews list cholinesterase inhibitors among the leading recognized causes of drug-induced hyperhidrosis (Cheshire & Fealey 2008).

The table summarises how each drug's official label describes sweating. Where a percentage exists, it is quoted directly; where the effect is listed qualitatively, no number is available and none is invented.

Rivastigmine is the drug in this class with a specific FDA-label figure for sweating. The chart shows the label's reported "sweating increased" rate at 6–12 mg/day in Alzheimer's disease trials versus placebo, and the corresponding figure in Parkinson's disease dementia trials.

How the class fits in the wider evidence

Cholinesterase inhibitors are one of four drug classes identified in a widely cited pharmacology review as leading causes of drug-induced hyperhidrosis, alongside SSRIs, opioids, and tricyclic antidepressants (Cheshire & Fealey 2008). Real-world reporting is consistent with this: sweating shows up in adverse-event databases across the class, and controlled human studies of pyridostigmine have shown measurable increases in sweat production under heat stress in exposed workers and military personnel (reviewed in Der2 2025).

Compared with antidepressants, where FDA labels quote sweating rates of roughly 5% to 21%, the label-quoted figures for cholinesterase inhibitors are lower (rivastigmine ~4%, donepezil not quantified). That does not necessarily mean less sweating in practice; it partly reflects how sweating was captured in each drug's own trials and how many gastrointestinal effects dominate the adverse-event list for this class.

Sweating as an overdose warning

Because sweating is a normal muscarinic effect of these drugs, a sudden increase can also be an early sign of cholinergic crisis in the setting of overdose or a large dose change. Every cholinesterase-inhibitor label warns about this: overdose can produce severe sweating along with vomiting, salivation, slow heart rate, low blood pressure, muscle weakness, and, at the extreme, respiratory failure. This is distinct from ordinary side-effect sweating and is a medical emergency. Anticholinergic drugs such as atropine are used as an antidote in that setting.

For routine, on-treatment sweating, the label figures above are the relevant reference. New, heavy or worsening sweating (especially with other symptoms) should be reviewed by the prescribing clinician rather than acted on independently.

Methodology and limitations

Drug-level information was taken directly from current FDA prescribing labels via DailyMed (rivastigmine, donepezil, pyridostigmine) and, where an FDA label figure is not published, from the manufacturer's product information and standard pharmacology references. Class-level framing draws on a peer-reviewed pharmacology review (Cheshire & Fealey 2008) and a recent updated review of pharmacological culprits of hyperhidrosis (2025). Each figure was traced to its source.

Limitations: FDA-label adverse-event rates come from each drug's own trials and reflect specific indications, doses, durations and patient populations, so they are not comparable head to head. Some labels (donepezil, galantamine) list sweating without a percentage; absence of a number does not imply the effect is uncommon. Because sweating is a class-shared muscarinic effect, cross-drug comparisons should be interpreted qualitatively. This page is verified label information for general education only; it is not medical advice and not a basis for starting, stopping or changing any medication.

Frequently asked questions

Do cholinesterase inhibitors cause sweating?

Yes. They are one of the four drug classes recognized as leading causes of drug-induced hyperhidrosis (Cheshire & Fealey 2008). The mechanism is on-target: by slowing the breakdown of acetylcholine at eccrine sweat glands, they increase sweat gland stimulation.

What are the label numbers for rivastigmine?

The rivastigmine (Exelon) FDA label reports "sweating increased" in 4% of Alzheimer's patients at 6–12 mg/day versus 1% on placebo. In Parkinson's disease dementia trials the label reports 2% on rivastigmine versus 1% on placebo.

Why doesn't donepezil's label give a percentage?

The donepezil (Aricept) label lists "sweating" under Skin and Appendages as an infrequent adverse reaction but does not quote an incidence figure. Absence of a percentage reflects how the effect was reported in the trials, not proof that it is rare.

Does pyridostigmine cause sweating?

Yes, as part of its expected muscarinic effects. The Mestinon label lists diaphoresis alongside salivation, increased gastrointestinal motility and other cholinergic effects, and warns that severe sweating can be a sign of cholinergic crisis in overdose.

Is this the same sweating as a cholinergic crisis?

No. Everyday, mild-to-moderate sweating on a stable dose reflects the drug's normal pharmacology. Sudden, severe sweating with vomiting, muscle weakness, slow heart rate or breathing difficulty can signal cholinergic crisis and is a medical emergency.

Is this medical advice?

No. These are verified label figures and pharmacology summaries for information only. They are not a basis for starting, stopping or changing any medication; those decisions belong with a prescribing clinician.

Sources

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

1. US Food and Drug Administration / DailyMed. Rivastigmine tartrate (Exelon) prescribing information: adverse reactions. "Sweating increased" 4% (rivastigmine 6–12 mg/day, n=1,189) vs 1% placebo (n=868) in Alzheimer's trials; 2% vs 1% in Parkinson's disease dementia trials. DailyMed
2. US Food and Drug Administration / DailyMed. Donepezil hydrochloride (Aricept) prescribing information: adverse reactions. "Sweating" listed under Skin and Appendages as an infrequent adverse reaction (no incidence percentage). Overdose section describes cholinergic crisis features including severe sweating. DailyMed
3. Bausch Health / US FDA. Mestinon (pyridostigmine bromide) prescribing information. Muscarinic side effects include nausea, vomiting, diarrhea, abdominal cramps, increased peristalsis, increased salivation, increased bronchial secretions, miosis and diaphoresis; overdose can produce cholinergic crisis. Product information
4. 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 recognized causes of hyperhidrosis. PubMed
5. Ahmad F, Alkatheeri A, et al. Pharmacological culprits of hyperhidrosis: an updated review of incidence, mechanisms, and management. Dermatological Reviews. 2025. Reviews cholinesterase-inhibitor mechanisms; cites experimental increases in sweat production with pyridostigmine under heat stress. (secondary) Full text
6. New Zealand Medicines and Medical Devices Safety Authority (Medsafe). Medicines that make you sweat: drug-induced hyperhidrosis. Prescriber Update, December 2024. Lists cholinesterase inhibitors among drug classes reported for hyperhidrosis in national pharmacovigilance data. (secondary) Medsafe (govt)

How to cite this page

Related reading on this site

• Drug-induced hyperhidrosis: an evidence overview by class
• Antidepressants and sweating: incidence by drug class
• Opioid-induced sweating: what the research shows
• Can medications cause excessive sweating?
• Talking to a clinician about sweating