Labetalol

Also indexed as: Normodyne®, Trandate®

Labetalol is used to treat high blood pressure.

Summary of Interactions with Vitamins, Herbs, and Foods
(for details about the summarized interactions, read the full article)

Beneficial May be Beneficial: Supportive interaction—Taking these supplements may support or otherwise help your medication work better.

Food
Avoid Avoid: Adverse interaction—Avoid these supplements when taking this medication because taking them together may cause undesirable or dangerous results.

High-potassium foods*

Pleurisy root*

Potassium
Depletion or interference

None known
Side effect reduction/prevention

None known
Reduced drug absorption/bioavailability

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.

Interaction with Dietary Supplements

Potassium
Three kidney transplant patients developed hyperkalemia (high blood potassium levels), a potentially dangerous condition, following intravenous administration of labetalol.1 Additional research is needed to determine whether taking oral labetalol together with potassium supplements might also lead to elevated blood levels of potassium. However, some other beta-blockers (called “nonselective” beta-blockers) are known to decrease the uptake of potassium from the blood into the cells,2 leading to 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

Interaction with Food and Other Compounds

Food
Taking labetalol with food greatly increases the absorption of the drug.5 Therefore, labetalol should be taken with a meal.

References

1. Arthur S, Greenberg A. Hyperkalemia associated with intravenous labetalol therapy for acute hypertension in renal transplant recipients. Clin Nephrol 1990;33:269–71.

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. Daneshmend TK, Roberts CJ. the influence of food on the oral and intravenous pharmacokinetics of a high clearance drug: a study with labetalol. Br J Clin Pharmacol 1982;14:73–8.