The objective of this drug is to produce a dilation in the pupil or a momentary paralysis, and it is used in ocular explorations.
Tropicamide, an anticholinergic generally administered under medical prescription, is presented in the form of ophthalmological drops that block the responses of the sphincter muscle of the iris.
It causes a dilation of the pupil or mydriasis and momentary paralysis of the ciliary muscle to make it impossible to accommodate the lens, known as cycloplegia.
- Benzalkonium Chloride, Sodium Edetate 2H2O, Polysorbate 80, Sodium Metabisulfite, and Sodium Chloride.
- In the ophthalmic solution, each ml contains 10 mg of tropicamide.
Due to its ability to dilate the pupil while maintaining its effects, this eye drop is usually used by specialists, temporarily and controlled, to:
- Thoroughly explore the eye’s interior, called the fundus, by dilating the pupil and blocking the sphincter muscle of the iris and the muscle of the ciliary body.
- In some surgical interventions where it is required that the pupil is dilated.
- It is sometimes used as a rapid-acting mydriatic in some pre and post-operative periods.
Mechanism of action
Tropicamide is an anticholinergic eye drop that works by blocking the responses of the sphincter muscle of the iris and the ciliary body muscle to stimulation caused by acetylcholine.
The solution used with a concentration of 0.5% produces dilatation of the pupil, and the attention of the solution at 1% has paralysis of the accommodation.
The tropicamide is not a medicine of daily use; it is the artificial tears or the refreshing eye drops; this is a medicine that should only be recommended and administered by a doctor.
Within the conditions for its correct administration, the following ones can be enunciated:
- It should only be used when the pupil must be dilated, usually to perform eye examinations such as the fundus or in some eye surgeries.
- The application should be made 15 to 20 minutes before the intervention.
- A specialized staff must carry out the application at all times.
- In the examinations where the refraction is carried out, the recommended dose is one drop of ophthalmic solution at 1%, and another decline is added five minutes later.
- The specialist’s intervention must be done in 20 or 30 minutes after giving the dots to the patient. If for any reason, the assessment lasts more than 30 minutes between the time of administration of the drops and the check made by the specialist, it is recommended to place an additional third drop.
- In children, the concentration of eye drops is usually reduced from 1 to 0.5%.
Tropicamide usually causes an increase in intraocular pressure very slightly.
So it would help if you were careful not to drive vehicles until you recover your average visual capacity.
When the recommended doses are applied, the adverse effects are only local.
Only in exceptional cases can systemic anticholinergic effects occur.
It is an infrequent occurrence that symptoms such as drowsiness, sedation, alteration of behavior, psychosis, headaches, and hallucinations (usually in children) occur at the central nervous system level.
At the cardiovascular level, it rarely causes tachycardia.
In the gastrointestinal tract, dry mouth.
And in the skin, exanthematic eruptions of rare occurrence.
Warnings and contraindications
This is a drug that requires a prescription for its acquisition and should be used with extreme caution:
During pregnancy: Women in pregnancy should restrict their use, as there are reports that there is a particular risk of causing damage to the fetus.
During breastfeeding: Breastfeeding is not recommended during treatment, as it is not known if it is excreted in breast milk.
Glaucoma: Its use is not recommended in patients diagnosed with glaucoma, as is the case of narrow-angle glaucoma.
Irritation: If the patient has swollen eyes, it is recommended to defer the test until inflammation has subsided since this medication can aggravate these symptoms.
Ability to drive: After administration, symptoms such as blurred vision and other visual disturbances may appear for a long time.
Generally, within a few hours of its application, the effects of this eye drop disappear entirely, and the patient returns to normal, but in some cases, it may last a little longer.
These effects affect the ability to use machinery or drive. You must not drive or use machines until you are optimal to do so.