labetalol, Normodyne, Trandate (cont.)

Pharmacy Author:
Medical and Pharmacy Editor:

SIDE EFFECTS AND PRECAUTIONS: The most common side effects of labetalol are:

Postural hypotension (a rapid decrease in blood pressure when going from the lying or seated position to the standing position that may cause light-headedness or fainting) occurs rarely. Patients should be observed for this possible side effect within two to four hours of the first labetalol dose and after any changes in dose.

Other important side effects include:

  • sexual dysfunction,
  • abnormal heart rhythm,
  • slow heart rate,
  • liver failure, and
  • allergic reactions.

GENERIC AVAILABLE: Yes

PRESCRIPTION: Yes

PREPARATION: Tablets: of 100, 200 and 300 mg; Injection: 5 mg/ml

STORAGE: Tablets should be stored between 20 C - 30 C (36 F - 86 F).

DOSING: The recommended starting oral dose of labetalol is 100 mg twice daily and the dose can be increased by 100 mg twice daily every 2-3 days based on the response of the blood pressure. Usual maintenance doses are 200-400 mg twice daily. Patients with severely high blood pressure may require 1.2 to 2.4 g daily.

Side effects may be less if labetalol is given in three daily doses rather than two. Stopping or changing the dose of the drug should be directed by a physician because serious side effects may occur. The initial intravenous dose of labetalol is 20 mg injected over 2 minutes. Additional injections of 40 or 80 mg may be administered every 10 minutes as needed up to a total dose of 300 mg. Labetalol also may be administered by intravenous infusion at 1-2 mg/minute.

Medically Reviewed by a Doctor on 12/30/2014


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