Effect
Timolol is a beta-blocker (beta-receptor antagonist) that is dripped into the eyes. The medication inhibits the excessive production of aqueous humor in the cavities (chambers) of the eyeball. This lowers the intraocular pressure.
Use
Timolol is present in medicines as timolol maleate. The active ingredient is mainly used in the form of eye drops. Solutions with an active ingredient content of 0.1 percent, 0.25 percent and 0.5 percent are available. Timolol tablets are only available in Germany. However, they are almost no longer prescribed because other beta-blockers have been much better studied.
Adults apply one drop twice a day into the lower conjunctival sac. To do this, pull the lower eyelid slightly downwards. Start with a low dosage because the effectiveness decreases over time and the dose can then be increased. The dropper should not touch the eye or skin so that it is not contaminated by bacteria.
Timolol can enter the systemic circulation. To keep this systemic uptake (absorption) as low as possible, press gently on the tear duct on the side of the eye facing the nose for one minute after instillation.
Timolol: Side effects
Common side effects of Timolol are irritation of the eye, for example temporary burning or stinging and visual disturbances.
Rarer side effects can be found in the package leaflet of your Timolol medication. Consult your doctor or ask at your pharmacy if you suspect any undesirable side effects.
Indications for use
Eye drops with timolol have the following indications:
- Increased intraocular pressure (ocular hypertension)
- Glaucoma (open-angle glaucoma)
- Glaucoma after lens removal (aphakic glaucoma)
- Childhood glaucoma when other treatments are not sufficient
Contraindications
Timolol must not be used if you are hypersensitive or allergic to the active ingredient or any other component of the medication. It is also not suitable for use in bronchial asthma, severe obstructive respiratory diseases (such as COPD) and severe allergic rhinitis. Patients with certain heart diseases (such as sinus bradycardia, AV block II or III degree, sick sinus syndrome) must not be prescribed Timolol. If there is a dystrophic disorder of the cornea (caused by deficiency or malnutrition), the eye drops cannot be used either.
Interactions
Interactions occur especially when several medications are used in the form of eye drops. Therefore, wait ten minutes after instilling Timolol before using other eye drops.
Some medications slow down the breakdown of timolol. This makes it more effective. Examples of such medications are quinidine (medication for cardiac arrhythmia), fluoxetine and paroxetine (antidepressants from the SSRI group) and bupropion (antidepressant and tobacco cessation medication).
Children
In exceptional cases, such as congenital or congenital glaucoma and juvenile glaucoma, children and adolescents can also be treated with timolol. However, this is always only a transitional therapy until suitable surgical measures can be taken. If an operation has already failed, Timolol can be used until further therapy has been determined.
To be on the safe side, treatment is started with just one drop in the lower conjunctival sac per day. This is important so that treatment can be stopped quickly if necessary. If the intraocular pressure does not drop sufficiently, one drop can be placed in the affected eye twice a day.
Pregnancy and breastfeeding
Timolol eye drops may be used throughout pregnancy and breastfeeding.
Remember to press gently on the tear duct for one minute immediately after instillation to reduce the absorption of Timolol into the body.
Dispensing regulations
Timolol is only available on prescription in Germany, Austria and Switzerland.
