Tropicamide
Tropicamide, which is to some extent structurally related to atropine, induces mydriasis and cycloplegia through paralysis of the parasympathetic system. Tropicamide is a parasympatholytic agent, which acts by blocking the action of the parasympathetic nervous system. As acetylcholine is the neurotransmitter at the receptor site of the parasympathetic nervous system, tropicamide competes with acetylcholine for uptake at the receptor sites, thereby blocking its action. The results are mydriasis, due to unopposed action of the dilator pupillae, and cycloplegia.Tropicamide visibly dilates the pupil after 5 minutes. It reaches its maximum diameter after 20-25 minutes and returns to its normal size within approx. 6 hours. The onset of the effect is rapid, but it disappears 45-60 minutes after the last instillation. The best time for retinoscopy is therefore approximately 20 minutes after the instillation of the last drop.
For refraction: instill 1 or 2 drops in the eye(s), repeated in 5 minutes. If patient is not seen within 20 to 30 minutes, an additional drop may be instilled to prolong mydriatic effect.For examination of the fundus: instill 1 drop 15 to 20 minutes prior to examination.
Atropine like substances, tricyclic antidepressants, numerous H1 antihistaminic substances, anti-cholinergic agents, anti-Parkinson drugs, phenothiazines and neuroleptic drugs are capable of reinforcing the effect of Tropicamin when taken or used.
Contraindicated in narrow angle glaucoma, hypersensitivity to any component of the product.
A slight burning sensation may occur for a short time after instillation into the eye. In children, psychotic episodes, behavioral changes and cardio-respiratory collapse may occur. This medicament impairs the performance and responsiveness while driving or operating machinery. It can also lead to an increase in intraocular pressure, allergic reaction, dryness of the mouth, tachycardia and headache.
Pregnancy Category C. Tropicamide should be given to a pregnant woman only if clearly needed. It is not known whether this drug is excreted in human milk. Because many drugs are excreted in human milk, caution should be exercised when tropicamide is administered to a nursing woman.
Where appropriate, the administration of an antidote (miotic) after the examination should be considered. To reduce excessive systemic absorption, the patient should compress the tear duct of the treated eye with the finger for 2-3 minutes immediately after the instillation of the eye drops. In older patients, mydriatic and cycloplegic drugs should generally be used with care.
Red face, accelerated pulse, dry mouth, reduced sweating and secretion as well as an increase in body temperature should be interpreted as a sign of overdosing, depending on the intensity of the symptoms. The emergency doctor should immediately be contacted in case of accidental ingestion. If required, the local effect can be counteracted or neutralized through the administration of a miotic agent (antidote).
Mydriatic and Cycloplegic agents
Store at room temperature and protect from light. It is desirable that the contents should not be used more than one month after first opening of the bottle.
{'Indications': 'Tropicamin sterile eye drops is used to dilate (enlarge) the pupil so that the doctor can see into the back of the eye. It is used before eye examinations, such as cycloplegic refraction and examination of the fundus of the eye. Tropicamin eye drops may also be used before and after eye surgery.'}