Tropicamide

3.75e-01 g/L

>42.7 [ug/mL] (The mean of the results at pH 7.4)

Breast Feeding; Lactation; Mydriatics; Muscarinic Antagonists; Parasympatholytics

FDA approved drugs -> Active ingredient

FDA approved drugs -> Active ingredient

Pharmaceuticals

Diagnostic agents > Ophthalmic medicines

170.4 Ų [M+Na]+ [CCS Type: TW; Method: calibrated with polyalanine and drug standards]

169.5 Ų [M+H]+ [CCS Type: TW; Method: calibrated with polyalanine and drug standards]

Danger

H302 (98.4%): Harmful if swallowed [Warning Acute toxicity, oral]

P233, P260, P261, P264, P264+P265, P270, P271, P272, P280, P284, P301+P317, P302+P352, P304+P340, P305+P351+P338, P317, P319, P321, P330, P332+P317, P333+P317, P337+P317, P342+P316, P362+P364, P403, P403+P233, P405, and P501 (click each P-code to see the statement)

Aggregated GHS information provided per 62 reports by companies from 9 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.

Although tropicamide is a short-acting drug, and the frequency of associated adverse events is rare, there are certain instances when reversal of mydriasis is necessary, including decreasing the risk of angle-closure glaucoma, improving blurry vision, and decreasing recovery time for patient comfort. Presumably, a cholinergic agent like pilocarpine should be able to undo the effects of an anticholinergic drug. However, several studies have reported conflicting pupillary responses. At times, only a partial reversal was observed.

S01FA06

S - Sensory organs

QS - Sensory organs

S01FA06

Tropicamide is an anticholinergic drug and that works by non‐selectively blocking muscarinic receptors to cause mydriasis and cycloplegia. It relaxes the pupillary sphincter to dilate the pupil. The onset of tropicamide‐induced mydriasis is about 10 to 15 minutes, with optimal effect occurring 25 to 30 minutes post-administration. Mydriasis caused by tropicamide wears off within four to eight hours, but it was seen up to 24 hours in some individuals. Tropicamide hinders accommodation by causing the contraction of the ciliary muscle. The cycloplegic effect occurs within 20 to minutes following administration, with a duration of action of four to 10 hours. Tropicamide can elevate intraocular pressure. The ophthalmic use of tropicamide is not typically associated with serious systemic adverse events. One randomized pilot study showed that oral tropicamide alleviated perceived symptoms of sialorrhea in patients with Parkinson's Disease: anticholinergics are believed to restore the dopaminergic to cholinergic activity imbalance in neurodegenerative diseases. Similarly in one case report, tropicamide administered via ophthalmic solution relieved clozapine-induced sialorrhea. Interestingly, in rodent models, tropicamide suppressed drug-induced tremulous jaw movements which are often used as a model of parkinsonian tremor: the significance of this finding requires further investigations.

Muscarinic acetylcholine receptors are involved in numerous ocular functions. The M₃ subtype is predominantly expressed by smooth muscle cells of the sphincter pupillae, which is a circular muscle of the iris, and ciliary muscles. In response to light or binding of acetylcholine, M₃ receptor signalling leads to contraction of the sphincter pupillae and pupil constriction. Contraction of the ciliary muscle via M₃ receptor signalling also leads to accommodation, adjusting the lens for near vision. The eye is also innervated by parasympathetic nerves: ciliary ganglion neurons project to the ciliary body and the sphincter pupillae muscle of the iris to control ocular accommodation and pupil constriction. Tropicamide is a non-selective muscarinic antagonist that binds to all subtypes of muscarinic receptors. By binding to muscarinic receptors, tropicamide relaxes the pupillary sphincter muscle and causes pupil dilation. By blocking the muscarinic receptors of the ciliary body, tropicamide also prevents accommodation. Like other muscarinic antagonists, tropicamide inhibits the parasympathetic drive, allowing the sympathetic nervous system responses to dominate. Tropicamide is thought to ameliorate sialorrhea by blocking M₄ receptors expressed on salivary glands and reducing hypersalivation.