Adult: As pilocarpine HCl or pilocarpine nitrate: Instill a 0.5-4% soln into affected eye/s up to 4 times daily, adjusted according to response.
Oral Dry mouth after radiotherapy for malignant neoplasms of the head and neck
Adult: Initially, 5 mg tid. If necessary, increase dose gradually after 4 wk until adequate response is achieved. Max: 10 mg tid.
Oral Sjogren's syndrome
Adult: For dry eyes and mouth: 5 mg 4 times daily. Max: 30 mg daily. Stop treatment if no improvement after 3 mth.
Hepatic Impairment
Oral:
Reduce dose in moderate to severe cirrhosis.
Administration
May be taken with or without food.
Contraindications
Conditions where pupillary constriction is undesirable (e.g. acute iritis, acute uveitis, anterior uveitis and some forms of secondary glaucoma); acute inflammatory disease of the anterior segment. Clinically significant uncontrolled cardiorenal disease, uncontrolled asthma, COPD and other chronic disease at risk for cholinergic agonists.
Special Precautions
Patient w/ history of retinal detachment, corneal or conjunctival damage; cognitive or psychiatric disorders, epilepsy, Parkinson’s disease; cholelithiasis or biliary tract disorders, hyperthyroidism; CV disease (e.g. HTN, hypotension); GI spasm, peptic ulceration; nephrolithiasis; resp disorders (e.g. controlled asthma, chronic bronchitis). Patients who are known to sweat excessively and who cannot drink enough liq. Hepatic or renal impairment. Pregnancy and lactation.
Not to be used in patients wearing soft contact lenses. This drug may cause miosis which may lead to blurred vision and difficulty w/ dark adaptation, do not drive or undertake hazardous tasks in poor illumination.
Monitoring Parameters
Monitor intraocular pressure. Perform funduscopic exam, visual field testing when necessary.
Overdosage
Symptoms: Muscarinic effects (e.g. abdominal cramps, diarrhoea, nausea, vomiting, involuntary defecation and urination, sweating, salivation, increased bronchial secretions, miosis, bradycardia and hypotension); nicotinic effects (e.g. twitching, fasciculations, generalised weakness). Management: Supportive treatment. Use parenteral atropine as an antidote to muscarinic effects. If resp depression is severe, institute artificial respiration.
Drug Interactions
Conduction disturbances w/ β-blockers. Concomitant admin of 2 miotics may increase risk of toxic reactions. Concurrent admin w/ drugs w/ parasympathomimetic effects may result in additive pharmacologic effects. May antagonise anticholinergic effects of atropine, inhaled ipratropium.
Food Interaction
Decreased rate of absorption w/ high fat meal.
Action
Description: Mechanism of Action: Pilocarpine is a tertiary amine parasympathomimetic that directly stimulates cholinergic receptors in the eyes, causing pupillary constriction, spasm of accommodation and lowering of intraocular pressure (IOP). Onset: Ophth: miosis: 10-30 min; IOP reduction: 60 min. Systemic: 20 min. Duration: Ophth: miosis: 4-8 hr; IOP reduction: 4-12 hr. Systemic: 3-5 hr. Pharmacokinetics: Absorption: Decreased rate of absorption w/ high fat meal. Distribution: Extensively distributed. Apparent volume of distribution: 2.1 L/kg. Metabolism: Primarily metabolised by CYP2A6 isoenzyme. Excretion: Via urine (approx 30%) as unchanged drug and inactive metabolites. Elimination half-life: 0.76-1.35 hr.
S01EB01 - pilocarpine ; Belongs to the class of parasympathomimetics. Used in the treatment of glaucoma and miosis. N07AX01 - pilocarpine ; Belongs to the class of other parasympathomimetics.
References
Anon. Pilocarpine (Ophthalmic). Lexicomp Online. Hudson, Ohio. Wolters Kluwer Clinical Drug Information, Inc. https://online.lexi.com. Accessed 01/02/2016.Anon. Pilocarpine (Systemic). Lexicomp Online. Hudson, Ohio. Wolters Kluwer Clinical Drug Information, Inc. https://online.lexi.com. Accessed 01/02/2016.Buckingham R (ed). Pilocarpine. Martindale: The Complete Drug Reference [online]. London. Pharmaceutical Press. https://www.medicinescomplete.com. Accessed 01/02/2016.Joint Formulary Committee. Pilocarpine. British National Formulary [online]. London. BMJ Group and Pharmaceutical Press. https://www.medicinescomplete.com. Accessed 01/02/2016.McEvoy GK, Snow EK, Miller J et al (eds). Pilocarpine. AHFS Drug Information (AHFS DI) [online]. American Society of Health-System Pharmacists (ASHP). https://www.medicinescomplete.com. Accessed 01/02/2016.