Pilocarpine
Pilocarpine hydrochloride
Also known as: Minims Pilocarpine · Pilocarpini hydrochloridum
Reviewed by the VetSheet Veterinary TeamUpdated Apr 5, 2026Evidence-based veterinary reference
Doses are a clinical reference for licensed veterinary professionals. Always confirm against the current label and the individual patient.
Dosing by species
🌎 NA — North America🌍 EU — Europe
Dogs
| Indication | Dose | Route | Frequency | Duration | Region |
|---|---|---|---|---|---|
| Management of glaucoma | Not specified in text | topical | Not specified in text | Not specified in text | 🌍 EU |
| Neurogenic keratoconjunctivitis sicca (KCS / dry eye) | Not specified in text | PO | Not specified in text | Not specified in text | 🌍 EU |
- Management of glaucoma: Produces miosis in 10-15 minutes lasting for 6-8 hours. Most common concentration used in dogs is 1%.
- Neurogenic keratoconjunctivitis sicca (KCS / dry eye): Increases lacrimation. Topical ophthalmic pilocarpine can also be used for this but can be irritant.
Doses are a clinical reference for licensed veterinary professionals. Always confirm against the current label and the individual patient.
Overview
Pilocarpine is a direct-acting parasympathomimetic agent used primarily in veterinary ophthalmology. It stimulates cholinergic receptors, leading to ciliary body muscle contraction and miosis, which facilitates improved aqueous humour outflow and lowers intraocular pressure.
While historically used for glaucoma management, it has largely been superseded by newer topical drugs like carbonic anhydrase inhibitors and prostaglandin analogues. Additionally, oral pilocarpine is utilized to stimulate lacrimation in dogs suffering from neurogenic keratoconjunctivitis sicca (KCS).
Clinical Warning: Pilocarpine is rarely used for ophthalmic purposes in cats due to a high risk of potential toxicity.
Mechanism of action
Pilocarpine is a direct-acting parasympathomimetic that stimulates cholinergic (muscarinic) receptors.
In the eye: Stimulates cholinergic receptors → ciliary body muscle contraction and miosis (pupil constriction) → opens the iridocorneal angle → improved aqueous humour outflow → decreased intraocular pressure (IOP).
Systemically/Orally: Stimulates exocrine glands → increased lacrimation and salivation.
Safety & warnings
Contraindications
- Uveitis
- Anterior lens luxation
Adverse effects
- Conjunctival hyperaemia (vasodilation)
- Local ocular irritation (due to low pH)
- Salivation
- Lacrimation
- Urinary incontinence
- Gastrointestinal disturbances (vomiting, diarrhea)
- Cardiac arrhythmias
Precautions
Species Warning: Avoid or use with extreme caution in cats due to potential toxicity.
Monitor for signs of systemic cholinergic toxicity, especially when administered orally for KCS or if ophthalmic drops are ingested.
Monitoring
- Intraocular pressure (IOP) if treating glaucoma
- Schirmer tear test (STT) if treating KCS
- Signs of systemic cholinergic toxicity (SLUDGE signs: Salivation, Lacrimation, Urination, Defecation, GI upset, Emesis)
Pharmacokinetics
Half-life
Absorption
Topical ophthalmic administration produces miosis within 10-15 minutes in dogs.
Distribution
Not specified in text.
Metabolism
Not specified in text.
Elimination
Duration of miotic effect in dogs is 6-8 hours.
Overdose
Overdosage or systemic absorption can lead to cholinergic toxicity (parasympathomimetic overdrive).
Clinical signs of systemic toxicity include:
- Salivation (drooling)
- Excessive lacrimation
- Urinary incontinence
- Gastrointestinal disturbances (vomiting, diarrhea)
- Cardiac arrhythmias
Available products
Formulations
- Ophthalmic solution 1%
- Ophthalmic solution 2%
- Ophthalmic solution 4%
Human-labeled
- Pilocarpine hydrochloride 1%, 2%, 4% ophthalmic solutions (e.g., Minims Pilocarpine)
Regulatory status
POM (Prescription Only Medicine)
POM-V (Prescription Only Medicine - Veterinarian)
No regulatory data for: 🇺🇸 US · 🇭🇰 HK · 🇹🇼 TW · 🇯🇵 JP · 🇰🇷 KR · 🇦🇺 AU
Storage & stability
Normal precautions should be observed. Available in 10 ml bottles and single-use vials.
Client information
Administration
- Eye drops: Wash hands before and after use. Do not let the dropper tip touch the eye or any other surface.
- Oral use (for dry eye): Administer exactly as prescribed by your veterinarian. Do not use eye drops orally unless specifically instructed to do so by your vet.
What to Watch For
- The eye drops can cause mild stinging or redness due to their low pH.
- Contact your veterinarian immediately if you notice signs of systemic toxicity, such as excessive drooling, vomiting, diarrhea, leaking urine, or changes in heart rate.
VetSheet drug reference is intended for licensed veterinary professionals as a clinical decision-support aid, not a substitute for professional judgement or the manufacturer’s current label.