atenolol and chlorthalidone, Tenoretic (cont.)

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Medical and Pharmacy Editor:

PRESCRIBED FOR: Atenolol/chlorthalidone is used to treat high blood pressure. Reducing blood pressure reduces the risk of strokes and heart attacks.

SIDE EFFECTS: Side effects of Atenolol/chlorthalidone are similar to side effects form the individual components and are:



PREPARATIONS: Tablets: atenolol 50mg and chlorthalidone 25mg; atenolol 100mg and chlorthalidone 25mg.

STORAGE: Tablets should be stored at room temperature, 15C and 30 C (59 F and 86 F).

DOSING: The recommended dose of atenolol/chlorthalidone is one tablet once daily starting with 50 mg/25 mg then increasing to 100 mg/25 mg if blood pressure control is not adequate.


  • Chlorthalidone can lower blood potassium and magnesium levels because both potassium and magnesium are lost in the urine.
  • Chlorthalidone reduces the kidney's ability to eliminate lithium (Lithobid) in the urine. As a result, patients taking chlorthalidone at the same time as drugs containing lithium may develop high levels of lithium and/or lithium toxicity.
  • Atenolol can mask the early warning symptoms of low blood sugar (hypoglycemia), and should be used with caution in patients receiving treatment for diabetes. Combining atenolol with other drugs that reduce blood pressure or slow heart rate may lead to excessive blood pressure reduction or low heart rate.
Medically Reviewed by a Doctor on 12/9/2014

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