atenolol, Tenormin (cont.)

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PREPARATIONS: Tablets: 25, 50 and 100 mg. Injection: 5 mg/10 ml

STORAGE: Atenolol should be store at room temperature 20 C to 25 C (68 F to 77 F).


  • The dose for treating high blood pressure or angina is 25-100 mg once daily.
  • Acute myocardial infarction (heart attack) is treated with two 5 mg injections administered 10 minutes apart. Ten minutes after the last injection, give 50 mg every 12 hours followed by 100 mg oral atenolol daily for 6-9 days. If atenolol injections are not appropriate, patients may be treated with 100 mg daily of oral atenolol for 7 days.

DRUG INTERACTIONS: Calcium channel blockers (CCBs) and digoxin (Lanoxin) can cause lowering of blood pressure and heart rate to dangerous levels when administered together with atenolol. Atenolol can mask the early warning symptoms of low blood sugar (hypoglycemia), and should be used with caution in patients receiving treatment for diabetes.

PREGNANCY: Atenolol may cause harm and growth retardation in the fetus when given to pregnant women.

NURSING MOTHERS: Atenolol is excreted in breast milk and my cause adverse effects in an infant being breastfed.

Medically reviewed by Omudhome Ogbru, PharmD

Reference: FDA Prescribing Information

Medically Reviewed by a Doctor on 4/13/2015

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