Dose:    1 drop each eye

Comments: Homatropine is an long acting anticholinergic agent used for mydriasis and cycloplegia during operative procedures.  The time for maximum mydriasis ranges from 40 to 60 minutes; the time for maximum cycloplegia ranges from 30 to 60 minutes.  The duration of action may last from 1 to 3 days.  To minimize absorption, use only one drop per eye and apply gentle digital pressure over the nasolacrimal sac for 2 to 3 minutes after installation. The anticholinergic effect blocks the response of the sphincter muscle of the iris and the accommodative muscle of the ciliary body. It acts less rapidly and has a longer duration of effect than topical cyclopentolate. Absorption can occur via any mucus membrane (i.e. mouth), and the antidote for overdose is Physostigmine as outlined below. Avoid contaminating the tip of the applicator with material from eye, fingers, or other source.

Toxicity: There is a possible association with the use of homatropine during the first three months of life and later development of amblyopia. This may also be true for infants with spastic paralysis or brain damage. Feeding intolerance may follow ophthalmic use of this product in neonates. It has been recommended that feedings be withheld for 4 hours after its use. Other reactions that are common to the cycloplegic mydriatics include tachycardia, headache, irritability, hyperpyrexia, vasodilatation, urinary retention, diminished GI motility often leading to abdominal distention, decreased secretions in the respiratory tract & the salivary glands, and skin rashes. Severe reactions are characterized by progressive respiratory depression and hypotension. If adverse reactions occur, the medication may be removed by irrigation of the eye with normal saline or water. Additional measures include treatment with physostigmine [0.02 mg/kg physostigmine salicylate (dilute 1 mg of physostigmine in 10 ml of sterile water) give 0.2 ml/kg over 2 minutes IV and repeat at 5 minute intervals if toxic symptoms persist and no cholinergic symptoms are produced (increased salivation or fasciculations). Physostigmine is contraindicated in hypotensive reactions (Facts and Comparisons, Inc. Drug Facts and Comparisons. Olin, B.R. ed. St. Louis, MO: Facts and Comparisons, Inc; 1997, page 486b).

Preparation: Available in 1 ml or 5 ml containers (Use only 2% in newborn). Store at room temperature. Discard it tip is contaminated.