Stinging, burning, lacrimation, lid muscle twitching, conjunctival and ciliary redness, brow ache, headache, and induced myopia with visual blurring may occur.
Activation of latent iritis or uveitis may occur.
As with all miotic therapy, retinal detachment has been reported occasionally.
Iris cysts may form, enlarge, and obscure vision. Occurrence is more frequent in children. The iris cyst usually shrinks upon discontinuance of the miotic. Rarely, the cyst may rupture or break free into the aqueous. Frequent examination for this occurrence is advised.
Lens opacities have been reported in patients on miotic therapy. Routine slit-lamp examinations, including the lens, should accompany prolonged use.
Paradoxical increase in intraocular pressure may follow anticholinesterase instillation. This may be alleviated by pupil-dilating medication.
Prolonged use may cause conjunctival thickening and obstruction of nasolacrimal canals.
Systemic effects, which occur rarely, are suggestive of increased cholinergic activity. Such effects may include nausea, vomiting, abdominal cramps, diarrhea, urinary incontinence, salivation, sweating, difficulty in breathing, bradycardia, or cardiac irregularities. Medical management of systemic effects may be indicated (see TREATMENT OF ADVERSE EFFECTS ).
TREATMENT OF ADVERSE EFFECTS
If HUMORSOL (demecarium) is taken systemically by accident, or if systemic effects occur after topical application in the eye or from accidental skin contact, administer atropine sulfate parenterally (intravenously if necessary) in a dose (for adults) of 0.4 to 0.6 mg or more. The recommended dosage of atropine in infants and children up to 12 years of age is 0.01 mg/kg repeated every two hours as needed until the desired effect is obtained, or adverse effects of atropine preclude further usage. The maximum single dose should not exceed 0.4 mg.
The use of much larger doses of atropine in treating anticholinesterase intoxication in adults has been reported in the literature. Initially 2 to 6 mg may be given followed by 2 mg every hour or more often, as long as muscarinic effects continue. The greater possibility of atropinization with large doses, particularly in sensitive individuals, should be borne in mind.
Pralidoxime** chloride has been reported to be useful in treating systemic effects due to cholinesterase inhibitors. However, its use is recommended in addition to and not as substitute for atropine.
A short-acting barbiturate is indicated if convulsions occur that are not entirely relieved by atropine. Barbiturate dosage should be carefully adjusted to avoid central respiratory depression. Marked weakness or paralysis of muscles of respiration should be treated promptly by artificial respiration and maintenance of a clear airway.
The oral LD 50 of HUMORSOL (demecarium) is 2.96 mg/kg in the mouse.
**PROTOPAM® Chloride (Pralidoxime Chloride). Ayerst Laboratories