Also indexed as: Blocadren, Timoptic
Timolol is a beta-blocker drug used to lower blood pressure in people with hypertension, treat people after heart attacks, and prevent migraine headaches. Timolol is available alone and in
a combination product used to lower blood pressure. Timolol is also available in eye drop and
eye gel preparations used to lower high internal eye pressure due to glaucoma and other conditions.
Summary of
Interactions with Vitamins, Herbs, and Foods
In some cases, an herb or supplement may appear in more than one category, which may seem
contradictory. For clarification, read the full article for details about the summarized
interactions.
 May Be Beneficial: Side effect
reduction/prevention—Taking these supplements may help reduce the likelihood and/or
severity of a potential side effect caused by the medication. |
Coenzyme Q10
|
| Depletion or interference |
None known
|
| Supportive interaction |
None known
|
| Reduced drug
absorption/bioavailability |
None known
|
| Adverse interaction |
None known
|
An asterisk (*) next to an item in the summary indicates that the
interaction is supported only by weak, fragmentary, and/or contradictory scientific
evidence.
Interactions with Dietary Supplements
Coenzyme
Q10
In a group of 16 glaucoma patients treated with a timolol eye preparation, six weeks of oral
coenzyme Q10 (90 mg per day) was reported to reduce timolol-induced cardiovascular side
effects without affecting intraocular pressure treatment.1
Potassium
Some beta-adrenergic blockers (called “nonselective” beta blockers) decrease the
uptake of potassium from the blood into the cells,2 leading to excess potassium in
the blood, a potentially dangerous condition known as hyperkalemia.3 People taking
beta-blockers should therefore avoid taking potassium supplements, or eating large quantities
of fruit (e.g., bananas), unless directed to do so by their
doctor.
Interactions with Herbs
Pleurisy root
As pleurisy root and other plants in the Aesclepius genus contain cardiac glycosides,
it is best to avoid use of pleurisy root with heart medications such as
beta-blockers.4
Interactions with Foods and Other Compounds
Food
Timolol may be taken with or without food.5
Alcohol
Timolol may cause drowsiness, dizziness, lightheadedness, or blurred vision.6
Alcohol may intensify these effects and increase the risk of accidental injury. To prevent
problems, people taking timolol should avoid alcohol.
References:1. Takahashi N, Iwasaka T, Sugiura T, et al. Effect of coenzyme Q10 on
hemodynamic response to ocular timolol. J Cardiovasc Pharmacol
1989;14:462–8.
2. Rosa RM, Silva P, Young JB, et al. Adrenergic modulation of extrarenal
potassium disposal. N Engl J Med 1980;302:431–4.
3. Lundborg P. The effect of adrenergic blockade on potassium
concentrations in different conditions. Acta Med Scand Suppl 1983;672:121–6
[review].
4. Newall CA, Anderson LA, Phillipson JD. Herbal Medicines: A Guide
for Health-Care Professionals. London: Pharmaceutical Press, 1996, 213–4.
5. Mantyla R, Mannisto P, Nykanen S, et al. Pharmacokinetic interactions
of timolol with vasodilating drugs, food and phenobarbitone in healthy human volunteers.
Eur J Clin Pharmacol 1983;24:227–30.
6. Threlkeld DS, ed. Diuretics and Cardiovasculars, Beta-Adrenergic
Blocking Agents. In Facts and Comparisons Drug Information. St. Louis, MO: Facts and
Comparisons, Feb 1993, 158q.