The usual starting dose of telmisartan is 40 mg once a day; blood pressure response is dose related over the range of 20 to 80 mg. Patients with depletion of intravascular volume should have the condition corrected or telmisartan tablets should be initiated under close medical supervision (see WARNINGS, Hypotension in Volume-Depleted Patients). Patients with biliary obstructive disorders or hepatic insufficiency should have treatment started under close medical supervision (see PRECAUTIONS).
Hydrochlorothiazide is effective in doses of 12.5 mg to 50 mg once daily.
To minimize dose-independent side effects, it is usually appropriate to begin combination therapy only after a patient has failed to achieve the desired effect with monotherapy. The side effects (see WARNINGS) of telmisartan are generally rare and apparently independent of dose; those of hydrochlorothiazide are a mixture of dose-dependent phenomena (primarily hypokalemia) and dose-independent phenomena (e.g., pancreatitis), the former much more common than the latter. Therapy with any combination of telmisartan and hydrochlorothiazide will be associated with both sets of dose-independent side effects. Telmisartan and hydrochlorothiazide tablets may be administered with other antihypertensive agents. Telmisartan and hydrochlorothiazide tablets may be administered with or without food.
Replacement Therapy
The combination may be substituted for the titrated components.
Dose Titration by Clinical Effect
Telmisartan and hydrochlorothiazide tablets are available as tablets containing either telmisartan 40 mg and hydrochlorothiazide 12.5 mg, or telmisartan 80 mg and hydrochlorothiazide 12.5 mg or 25 mg. A patient whose blood pressure is not adequately controlled with telmisartan monotherapy 80 mg (see above) may be switched to telmisartan and hydrochlorothiazide tablets, telmisartan 80 mg/hydrochlorothiazide 12.5 mg once daily, and finally titrated up to 160/25 mg, if necessary.
A patient whose blood pressure is inadequately controlled by 25 mg once daily of hydrochlorothiazide may be switched to telmisartan 80 mg/hydrochlorothiazide 12.5 mg or telmisartan 80 mg/hydrochlorothiazide 25 mg tablets once daily. The clinical response to telmisartan and hydrochlorothiazide tablets should be subsequently evaluated and if blood pressure remains uncontrolled after 2 to 4 weeks of therapy, the dose may be titrated up to 160/25 mg, if necessary. Those patients controlled by 25 mg hydrochlorothiazide but who experience hypokalemia with this regimen, may be switched to telmisartan 80 mg/ hydrochlorothiazide 12.5 mg tablets once daily, reducing the dose of hydrochlorothiazide without reducing the overall expected antihypertensive response.
Patients with Renal Impairment
The usual regimens of therapy with telmisartan and hydrochlorothiazide tablets may be followed as long as the patient's creatinine clearance is >30 mL/min. In patients with more severe renal impairment, loop diuretics are preferred to thiazides, so telmisartan and hydrochlorothiazide tablets are not recommended.
Patients with Hepatic Impairment
Telmisartan and hydrochlorothiazide tablets are not recommended for patients with severe hepatic impairment. Patients with biliary obstructive disorders or hepatic insufficiency should have treatment started under close medical supervision using the 40/12.5 mg combination (see PRECAUTIONS).