Tropicamide, sold under the brand name Mydriacyl among others, is a medication used to
dilate the pupil and help with
examination of the eye.[3] Specifically it is used to help examine the
back of the eye.[4] It is applied as
eye drops.[3] Effects occur within 40 minutes and last for up to a day.[3]
Tropicamide is an
antimuscarinic drug that produces short acting
mydriasis (dilation of the
pupil) and
cycloplegia[7] when applied as
eye drops. It is used to allow better examination of the
lens,
vitreous humor, and
retina. Due to its relatively short duration of effect (4–8 hours), it is typically used during
eye examinations such as the
dilated fundus examination, but it may also be used before or after
eye surgery. Cycloplegic drops are often also used to treat anterior
uveitis, decreasing risk of posterior
synechiae and decreasing inflammation in the anterior chamber of the eye.
Tropicamide is occasionally administered in combination with
p-hydroxyamphetamine (brand name
Paremyd), which is a
sympathomimetic. The use of the sympathomimetic drug causes the iris dilator muscle to be directly stimulated, causing increased dilation. In the United States, the sympathomimetic drop most commonly used along with tropicamide, is 2.5%
phenylephrine hydrochloride (brand name AK-Dilate).
Side effects
Tropicamide induces transient stinging and a slight and transient rise in
intraocular pressure in the majority of patients. It may cause redness or
conjunctivitis (inflammation) and also
blurs near vision for a short while after instillation (care must be taken, and the patient must only drive when vision returns to normal). Tropicamide may, in very rare cases,[8] cause an attack of
acute angle-closure glaucoma. This tends to be in patients with narrow
anterior chamberangles, and closure risk must be assessed by the practitioner prior to instillation.
Tropicamide is often preferred to
atropine because atropine has a longer
half-life, causing prolonged dilation and blurry vision for up to a week. Atropine has less
sting effect, but can be toxic or fatal if ingested in large quantities by children or adults.
Tropicamide is sometimes abused (injected intravenously e.g. by
insulin syringe) as an inexpensive recreational
deliriant drug (along with
naphazoline). This was initially reported in Russia, but has subsequently spread to various other countries in the former Soviet Union and around Europe, and later in the United States.[10][11][12][13]
^World Health Organization (2019). World Health Organization model list of essential medicines: 21st list 2019. Geneva: World Health Organization.
hdl:10665/325771. WHO/MVP/EMP/IAU/2019.06. License: CC BY-NC-SA 3.0 IGO.
^Vuori ML, Kaila T, Iisalo E, Saari KM (1994-01-01). "Systemic absorption and anticholinergic activity of topically applied tropicamide". Journal of Ocular Pharmacology. 10 (2): 431–437.
doi:
10.1089/jop.1994.10.431.
PMID8083562.
^Bersani FS, Imperatori C, Prilutskaya M, Kuliev R, Corazza O (July 2015). "Injecting eye-drops: a mini-review on the non-clinical use of tropicamide". Hum Psychopharmacol. 30 (4): 262–4.
doi:
10.1002/hup.2481.
PMID26216560.
S2CID190289.
^Rote Liste (in German). Vol. 57. Frankfurt/Main: Rote Liste Service GmbH. 2017. p. 224.
ISBN978-3-946057-10-9. Arzneimittelverzeichnis für Deutschland (einschließlich EU-Zulassungen und bestimmter Medizinprodukte)
External links
"Tropicamide". Drug Information Portal. U.S. National Library of Medicine.