Muscarinic Agonist — Dry Mouth / Sjögren's Pregnancy: Pregnancy Category C (US labelling). No adequate and well-controlled studies in pregnant women; use during pregnancy only if the potential benefit justifies the potential risk to the fetus.

Pilocarpine

Brand names: Salagen, Pilocarpine HCl

Pilocarpine is a cholinergic agent used systemically to treat dry mouth (xerostomia), including that following head and neck radiotherapy or due to Sjogren's syndrome.

Auto-extracted from the source labelling — not yet independently clinician-verified. These values were distilled from the UK SPC (or the US label where noted) but have not had a clinician sign-off. Confirm against the current SmPC before prescribing.

Adult dose

Dose: 5 mg

Route: Oral

Frequency: Three times a day (head & neck cancer xerostomia); four times a day (Sjogren's syndrome)

Max: Not to exceed 10 mg per dose; usual range 15-30 mg per day

US oral tablet labelling used because the supplied UK eMC bundle covered only OPHTHALMIC pilocarpine (glaucoma eye drops), not the oral ENT/xerostomia (dry mouth) indication - verify against UK SPC. Head & neck cancer patients (radiation-induced dry mouth): recommended initial dose 5 mg three times a day, titrate to therapeutic response and tolerability; usual range 15-30 mg/day; at least 12 weeks of uninterrupted therapy may be needed to assess response. Sjogren's syndrome: 5 mg four times a day. Moderate hepatic impairment: start 5 mg twice daily. Use lowest tolerated effective dose for maintenance.

Dose auto-extracted from UK Summary of Product Characteristics (SPC) via the eMC; US FDA prescribing information (openFDA / DailyMed) — cross-check; US labelling may differ from UK — not yet clinician-verified. Always confirm against the product SmPC and your local formulary before prescribing.

Contraindications

Uncontrolled asthma
Known hypersensitivity to pilocarpine
When miosis is undesirable, e.g. acute iritis and narrow-angle (angle-closure) glaucoma

Side effects

Sweating (very common)
Nausea, rhinitis, diarrhoea
Chills, flushing, urinary frequency
Dizziness, asthenia
Headache, dyspepsia, lacrimation

Interactions

Beta-adrenergic antagonists: administer with caution due to possible conduction disturbances
Drugs with parasympathomimetic effects: additive pharmacologic effects
Anticholinergic drugs (e.g. atropine, inhaled ipratropium): pilocarpine may antagonise their anticholinergic effects

Clinical monograph

How it works

It is a muscarinic receptor agonist that stimulates exocrine secretion, increasing saliva production from residual functioning salivary gland tissue.

Prescribing in practice

It is contraindicated in uncontrolled asthma and in acute or narrow-angle glaucoma owing to its cholinergic effects.
Common cholinergic adverse effects include sweating, nausea, urinary frequency and rhinitis.
Caution is needed in patients with cardiovascular disease, chronic bronchitis or other conditions sensitive to increased cholinergic tone.

Monitoring

Monitor for the response of dry-mouth symptoms and for cholinergic adverse effects such as excessive sweating or palpitations.

Counselling the patient

Increased sweating is a common effect, so maintain an adequate fluid intake.
Tell us if you experience wheezing, blurred vision or a fast heartbeat.
Take it as directed and report any troublesome side effects.

Evidence & guidelines

Use is established for radiotherapy-induced and Sjogren's-related xerostomia; refer to the SPC for contraindications and cautions.

Reference: Fox et al. (1996) NEJM Pilocarpine for Sjögren's; BSAC/BSR Sjögren's Syndrome Guidelines 2017; Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. The structured dose values shown have been reviewed by a clinician. Monograph status: clinician-reviewed (2026-07-04).

Curated clinical cross-links plus same-class fallbacks.

Calculators

Pathways