Meds and you

27 September 2013


Timolol is a beta-receptor blocker. Beta-receptor blockers are drugs that act on beta-receptors in the heart.


Timolol is the active ingredient of Glaucosan drops (Nappi code: 821624-008), Timoptol ophthalmic solution (Nappi code: 770833-004, 770841-007) & Timoptol ZE Gellan Solution (Nappi code: 819816-019, 819824-003).

General information
Timolol is a beta-receptor blocker. Beta-receptor blockers are drugs that act on beta-receptors in the heart, thereby reducing its force and speed of contraction, and on blood vessels, preventing vasodilatation. In the form of eye drops, beta-receptor blockers are used to reduce fluid pressure within the eye.

In South Africa timolol is registered for the reduction of raised intra-ocular pressure and for the treatment of glaucoma.

For this medication to be effective, it has to be taken regularly, even if you do not notice an immediate effect.

It should be noted that because this drug may cause dizziness, light-headedness and/or visual disturbances, driving and any hazardous tasks should be avoided until you know how this medication affects you.

Timolol ophthalmic drops should not be used if you have soft contact lenses in your eyes.

How does timolol work?
Timolol as an eye drop causes blood vessels in the eye to narrow. By narrowing these blood vessels, less fluid passes through the blood vessel into the eyeball, thereby reducing pressure within the eye. It furthermore reduces the production of aqueous humour within the eyeball.

Fast facts

Drug schedule: schedule 3
Available as: timolol is available as eye drops.
What does it do? Timolol reduces pressure inside the eyes.
Overdose risk: medium
Dependence risk: low
Is timolol available as a generic? yes
Is timolol available on prescription only? yes

User information

Stopping this medicine: do not stop taking this drug without consulting your doctor.
Prolonged use: regular ophthalmic examinations are advised with long-term use. A decreased effect of this medication may furthermore be noted with prolonged use.

Special precautions
Consult your doctor before using this drug if:

  • you have or had heart disease
  • you have asthma
  • you have chronic bronchitis
  • you have diabetes
  • you have a slow heart rate (<50 beats per minute)

Pregnancy: avoid. Potential risk to the foetus has been reported. Consult your doctor before use, or if you are planning to fall pregnant.
Breastfeeding: avoid. This medication is passed through breast milk and may affect your baby adversely. Consult your doctor before use.
Porphyria: this medication is considered safe to use
Infants and children: use only as directed and under the supervision of a specialist.
The elderly: caution is advised in the elderly as side effects are more likely to occur.
Alcohol: no special precautions need to be taken.

Possible side effects


Side Effect
Consult your doctor
Only if severe
In all cases
blurred vision
dry eyes
corneal disorders

Although this is an eye drop, systemic effects cannot be excluded and these may include low blood pressure, a slow heart rate, heart rhythm disturbances, congestive heart failure, chest pain, palpitations, difficulty breathing, coughing, muscle weakness, cold hands and feet, headaches and even a heart attack.


Drug interactions


reserpine lowering of blood pressure, slow heart rate and dizziness may occur
digoxin increased side effects of digoxin
verapamil increased side effects of verapamil
oral beta-receptor blockers increased risk of side effects with both drugs

Disease interactions
Consult your doctor before using this drug if you have, or have had heart disease, you have asthma, chronic bronchitis, diabetes or if you have a slow heart rate (<50 beats per minute).

Overdose action
A small overdose is no cause for concern. In case of intentional large overdose, seek emergency medical attention.


This material is not intended to substitute medical advice, but is for informational purposes only. Please consult a physician for specific treatment and recommendations.



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