Medications and Drugs
GENERIC NAME: propranolol
BRAND NAMES: Inderal, Inderal LA
DRUG CLASS AND MECHANISM: Propranolol is a beta-
adrenergic
blocking agent. Propranolol blocks the action of the sympathetic
nervous
system, a portion of the involuntary nervous system. The sympathetic nervous system stimulates the pace of the heart beat. By blocking the action of these nerves, propranolol reduces the heart rate and is
useful in
treating abnormally rapid heart rhythms. Propranolol also
reduces the
force of heart muscle contraction and lowers blood pressure. By
reducing
the heart rate and the force of muscle contraction, propranolol
reduces
heart muscle oxygen demand. Since angina occurs when oxygen
demand of the
heart exceeds supply, propranolol is helpful in treating
angina.
PRESCRIPTION: yes
GENERIC AVAILABLE: yes
PREPARATIONS: Tablets: 10 mg, 20 mg, 40 mg, 60 mg, 80
mg.
Capsules (long-acting): 60 mg, 80 mg, 120 mg, 160 mg.
STORAGE: Tablets and capsules should be stored at room
temperature in a tightly closed container.
PRESCRIBED FOR: Propranolol is prescribed for patients
with high
blood pressure (hypertension). It is also used to treat chest
pain (angina
pectoris) related to coronary artery disease. Propranolol is
also useful
in slowing and regulating certain types of abnormally rapid
heart rates
(tachycardias). Other uses for propranolol include the
prevention of
migraine headaches and the treatment of certain types of
tremors (familial
or hereditary essential tremors). Propranolol is commonly used in persons with thyrotoxicosis (high blood levels of thyroid
hormone) to slow down rapid heart rate and tremor.
DOSING: Should be taken before meals or at bedtime.
DRUG INTERACTIONS: Propranolol can aggravate breathing
difficulties in patients with asthma, chronic bronchitis, or
emphysema. In
patients with existing slow heart rates (bradycardias) and
heart blocks
(defects in the electrical conduction of the heart),
propranolol can cause
dangerously slow heart rates, and even shock. Propranolol
reduces the
force of heart muscle contraction and can aggravate symptoms of
heart
failure. Calcium channel blockers, digoxin (Lanoxin), and
haloperidol (Haldol) can cause lowering of blood pressure and heart rate to
dangerous
levels when administered together with propranolol. In patients
with
coronary artery disease, abruptly stopping propranolol can
suddenly worsen
angina, and occasionally precipitate heart attacks. If it is
necessary to
discontinue propranolol, its dosage can be reduced gradually
over several
weeks. Propranolol can mask the early warning symptoms of low
blood sugar
(hypoglycemia), and should be used with caution in patients
receiving
treatment for diabetes. Safe use in children has not been
established. It
is not habit forming.
Many medicines interact with propranolol. Alcohol and aluminum
containing antacids reduce the absorption of propranolol.
Phenytoin (Dilantin), phenobarbital, and rifampin reduce the blood levels
of
propranolol. Cimetidine (Tagamet) and chlorpromazine increase
the blood
levels of propranolol. Propranolol increases the blood levels
of certain
medicines such as theophylline and lidocaine.
PREGNANCY: Safe use during pregnancy has not been
established.
SIDE EFFECTS: Propranolol is generally well tolerated,
and side effects are mild and transient. Rare side effects include abdominal
cramps, diarrhea, constipation, fatigue, insomnia, nausea,
depression, dreaming, memory loss,
fever, impotence, lightheadedness, slow
heart rate,
low blood pressure, numbness, tingling, cold extremities, sore
throat, and
shortness of breath or wheezing.
Reference: FDA Prescribing Information
Last Editorial Review: 4/20/2001
Report Problems to the Food and Drug Administration
You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.
- metoprolol, Lopressor, Toprol XL - Learn more about Metoprolol, a drug to treat high blood pressure, heart pain, abnormal rhythms of the heart, and some neurological conditions. Information includes a description, generic and brand names, drug class and mechanism, preparations, storage, reasons for prescription, dosing, drug interactions, effect on pregnancy, and common side effects.
- High Blood Pressure - Learn about high blood pressure symptoms like headache, dizziness, shortness of breath, blurred vision and more. Causes, and normal blood pressure information is included.
- Drug Interactions - Learn about potential drug interactions you may be exposed to. Drug interactions can occur with prescription drugs, OTC medication, vitamins, herbs, and supplements.
Latest Medical News
Back to Medications Index
Heart RSS