Tenormin | Atenolol

Medication class: beta-adrenergic receptor blocking agent or beta blocker
Manufacturer: AstraZeneca
Approval date: August, 1981

What is Tenormin and how does it work

Tenormin belongs to a group of drugs known as beta-adrenergic blocking agents or beta blockers. Beta receptors are located in the heart, blood vessels, airways, and some other tissues. They control heart rate, breathing, blood pressure, and several other functions when stimulated by epinephrine (adrenaline), which is a hormone. Epinephrine constricts blood vessels, causing blood pressure to rise, and increases heart rate by stimulating beta receptors. Tenormin reduces blood pressure and slows heart rate by preventing epinephrine from attaching to beta receptors in the heart.

What does Tenormin treat

• Hypertension (high blood pressure)
• Angina Pectoris (chest pain) due to coronary atherosclerosis (blocked blood vessels in the heart).
• Acute Myocardial Infarction (heart attack)

How effective is Tenormin

• The effect of Tenormin is apparent within one hour of oral administration of a single dose. The effect is maximal within 2-4 hours of administration and lasts for at least 24 hours.
• In patients who suffered a heart attack, Tenormin Injection 5-10 mg plus Tenormin tablets 50 mg every 12 hours orally on the first study day followed by Tenormin tablets 100 mg or 50 mg twice daily between days 2-7 produced a significant 15% reduction in death rate as compared to conventional therapy.
• Tenormin given as a single daily dose was an effective antihypertensive agent providing 24-hour reduction of blood pressure compared to placebo.
• Doses above 100 mg daily do not provide additional blood pressure reduction.

What are interesting facts about Tenormin

• Administering Tenormin after a heart attack can prevent death.
• It is available in generic formulation.
• It normal doses it not beta receptors in the airways and therefore is less likely than propranolol (another beta blocker) to reduce breathing in individuals with asthma.

How is Tenormin dosed and administered

Tenormin is available as 25 mg, 50 mg and 100 mg tablets. The intravenous formulation has been discontinued.

• Hypertension:For high blood pressure the initial dose for adult patients is one tablet is 50 mg given once daily. The dosage can be increased to 100 mg a day within two weeks if response is not adequate.
• Angina Pectoris:The initial dosage for adult patients should be one 50 mg a day. The dosage can be increased to 100 mg daily if response is not adequate. Some patients may require 200 mg daily.
• Acute Myocardial Infarction:100 mg a day as soon as possible for at least 7 days.

What are the side effects of Tenormin

Common: Dizziness, vertigo, tiredness, weakness, depression, insomnia, diarrhea, nausea, leg pain, cold extremities, bronchospasm, shortness of breath, low blood pressure, and slow heart rate.

Serious: Congestive heart failure (CHF), heart block, abnormal heart beats and rhythm, severe reduction in heart rate, allergic reactions.

Chest pain, heart attack, or abnormal heart beats may occur if individuals with coronary heart disease abruptly stop Tenormin. Discontinue gradually.

Tenormin drug interactions

• Calcium channel blockers and digoxin (Lanoxin): Tenormin when given in combination with these can cause a fatal drop in heart rate and blood pressure.
• Administer cautiously to diabetic patients since it can mask symptoms of hypoglycemia (low blood sugar).

References: Tenormin FDA Prescribing Information.