Dosage should be determined by individual titration (see INDICATIONS AND USAGE).

Hydrochlorothiazide is usually given at a dosage of 12.5 to 50 mg per day. The usual initial dosage of Lopressor is 100 mg daily in single or divided doses. Dosage may be increased gradually until optimum blood pressure control is achieved. The effective dosage range is 100 to 450 mg per day. While once-daily dosing is effective and can maintain a reduction in blood pressure throughout the day, lower doses (especially 100 mg) may not maintain a full effect at the end of the 24-hour period, and larger or more frequent daily doses may be required. This can be evaluated by measuring blood pressure near the end of the dosing interval to determine whether satisfactory control is being maintained throughout the day. Beta1 selectivity diminishes as dosage of Lopressor is increased.

The following dosage schedule may be used to administer from 100 to 200 mg of Lopressor per day and from 25 to 50 mg of hydrochlorothiazide per day:

Dosing regimens that exceed 50 mg of hydrochlorothiazide per day are not recommended. When necessary, another antihypertensive agent may be added gradually, beginning with 50% of the usual recommended starting dose to avoid an excessive fall in blood pressure.