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Micardis® HCT (telmisartan and hydrochlorothiazide) tablets has been evaluated for safety in over 1700 patients, including 716 treated for over six months and 420 for over one year. In clinical trials with MICARDIS HCT tablets, no unexpected adverse events have been observed. Adverse experiences have been limited to those that have been previously reported with telmisartan and/or hydrochlorothiazide. The overall incidence of adverse experiences reported with the combination was comparable to placebo. Most adverse experiences were mild in intensity and transient in nature and did not require discontinuation of therapy.
Adverse events occurring at an incidence of 2% or more in patients treated with telmisartan/hydrochlorothiazide and at a greater rate than in patients treated with placebo, irrespective of their causal association, are presented in Table 1.
TABLE 1 : Adverse Events Occurring in ≥ 2%
of Telmisartan/Hydrochlorothiazide (HCTZ) Patients*
|Body as a whole|
|Central/peripheral nervous system|
|Respiratory system disorder|
|Upper respiratory tract infection||8||7||7||10|
|* includes all doses of telmisartan (20-160 mg), hydrochlorothiazide (6.25-25 mg), and combinations thereof|
The following adverse events were reported at a rate less than 2% in patients treated with telmisartan/hydrochlorothiazide and at a greater rate than in patients treated with placebo: back pain, dyspepsia, vomiting, tachycardia, hypokalemia, bronchitis, pharyngitis, rash, hypotension postural, abdominal pain.
Finally, the following adverse events were reported at a rate of 2% or greater in patients treated with telmisartan/hydrochlorothiazide, but were as, or more common in the placebo group: pain, headache, cough, urinary tract infection.
Adverse events occurred at approximately the same rates in men and women, older and younger patients, and black and non-black patients.
In controlled trials (n=1017), 0.3% of patients treated with Micardis® HCT (telmisartan and hydrochlorothiazide) tablets 40/12.5 mg, 80/12.5 mg or 80/25 mg discontinued due to orthostatic hypotension, and the incidence of dizziness was 4%, 7%, and 1%, respectively.
Other adverse experiences that have been reported with telmisartan, without regard to causality, are listed below:
Vascular : cerebrovascular disorder
A single case of angioedema was reported (among a total of 3781 patients treated with telmisartan).
Other adverse experiences that have been reported with hydrochlorothiazide, without regard to causality, are listed below:
Body as a whole : weakness
Hypersensitivity : purpura, photosensitivity, urticaria, necrotizing angiitis (vasculitis and cutaneous vasculitis), fever, respiratory distress including pneumonitis and pulmonary edema, anaphylactic reactions
Musculoskeletal : muscle spasm
Nervous System/Psychiatric : restlessness
Renal : renal failure, renal dysfunction, interstitial nephritis
The following adverse reactions have been identified during post-approval use of Micardis® (telmisartan) tablets. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to estimate reliably their frequency or establish a causal relationship to drug exposure. Decisions to include these reactions in labeling are typically based on one or more of the following factors: (1) seriousness of the reaction, (2) frequency of reporting, or (3) strength of causal connection to MICARDIS tablets. The most frequently spontaneously reported events include: headache, dizziness, asthenia, coughing, nausea, fatigue, weakness, edema, face edema, lower limb edema, angioneurotic edema, urticaria, hypersensitivity, sweating increased, erythema, chest pain, atrial fibrillation, congestive heart failure, myocardial infarction, blood pressure increased, hypertension aggravated, hypotension (including postural hypotension), hyperkalemia, syncope, dyspepsia, diarrhea, pain, urinary tract infection, erectile dysfunction, back pain, abdominal pain, muscle cramps (including leg cramps), myalgia, bradycardia, eosinophilia, thrombocytopenia, uric acid increased, abnormal hepatic function/liver disorder, renal impairment including acute renal failure, anemia, increased CPK, anaphylactic reaction, tendon pain (including tendonitis, tenosynovitis), drug eruption (toxic skin eruption mostly reported as toxicoderma, rash, and urticaria), hypoglycemia (in diabetic patients), and angioedema (with fatal outcome).
Rare cases of rhabdomyolysis have been reported in patients receiving angiotensin II receptor blockers, including MICARDIS tablets.
Clinical Laboratory Findings
In controlled trials, clinically relevant changes in standard laboratory test parameters were rarely associated with administration of Micardis® HCT (telmisartan and hydrochlorothiazide) tablets.
Hemoglobin and Hematocrit : Decreases in hemoglobin ( ≥ 2 g/dL) and hematocrit ( ≥ 9%) were observed in 1.2% and 0.6% of telmisartan/hydrochlorothiazide patients, respectively, in controlled trials. Changes in hemoglobin and hematocrit were not considered clinically significant and there were no discontinuations due to anemia.
Creatinine, Blood Urea Nitrogen (BUN) : Increases in BUN ( ≥ 11.2 mg/dL) and serum creatinine ( ≥ 0.5 mg/dL) were observed in 2.8% and 1.4%, respectively, of patients with essential hypertension treated with MICARDIS HCT tablets in controlled trials. No patient discontinued treatment with MICARDIS HCT tablets due to an increase in BUN or creatinine.
Liver Function Tests : Occasional elevations of liver enzymes and/or serum bilirubin have occurred. No telmisartan/hydrochlorothiazide treated patients discontinued therapy due to abnormal hepatic function.
Serum Electrolytes : See PRECAUTIONS.
Read the Micardis HCT (telmisartan, hydrochlorothiazide) Side Effects Center for a complete guide to possible side effects
Digoxin: When telmisartan was co-administered with digoxin, median increases in digoxin peak plasma concentration (49%) and in trough concentration (20%) were observed. It is, therefore, recommended that digoxin levels be monitored when initiating, adjusting, and discontinuing telmisartan to avoid possible over-or under-digitalization.
Lithium: Reversible increases in serum lithium concentrations and toxicity have been reported during concomitant administration of lithium with angiotensin converting enzyme inhibitors. Cases have also been reported with angiotensin II receptor antagonists including telmisartan. Because lithium should not be used with diuretics, the use of lithium with telmisartan and hydrochlorothiazide is not recommended.
Non-Steroidal Anti-Inflammatory Agents including Selective Cyclooxygenase-2 Inhibitors (COX-2 Inhibitors): In patients who are elderly, volume-depleted (including those on diuretic therapy), or with compromised renal function, co-administration of NSAIDs, including selective COX-2 inhibitors, with angiotensin II receptor antagonists, including telmisartan, may result in deterioration of renal function, including possible acute renal failure. These effects are usually reversible. Monitor renal function periodically in patients receiving telmisartan and NSAID therapy.
The antihypertensive effect of angiotensin II receptor antagonists, including telmisartan may be attenuated by NSAIDs including selective COX-2 inhibitors.
Ramipril and Ramiprilat: Co-administration of telmisartan 80 mg once daily and ramipril 10 mg once daily to healthy subjects increases steady-state Cmax and AUC of ramipril 2.3 and 2.1 fold, respectively, and Cmax and AUC of ramiprilat 2.4 and 1.5 fold, respectively. In contrast, Cmax and AUC of telmisartan decrease by 31% and 16%, respectively. When co-administering telmisartan and ramipril, the response may be greater because of the possibly additive pharmacodynamic effects of the combined drugs, and also because of the increased exposure to ramipril and ramiprilat in the presence of telmisartan.
Warfarin: Telmisartan administered for 10 days slightly decreased the mean warfarin trough plasma concentration; this decrease did not result in a change in International Normalized Ratio (INR).
Other Drugs: Co-administration of telmisartan did not result in a clinically significant interaction with acetaminophen, amlodipine, glibenclamide, simvastatin, hydrochlorothiazide or ibuprofen. Telmisartan is not metabolized by the cytochrome P450 system and had no effects in vitro on cytochrome P450 enzymes, except for some inhibition of CYP2C19. Telmisartan is not expected to interact with drugs that inhibit cytochrome P450 enzymes; it is also not expected to interact with drugs metabolized by cytochrome P450 enzymes, except for possible inhibition of the metabolism of drugs metabolized by CYP2C19.
When administered concurrently, the following drugs may interact with thiazide diuretics:
Alcohol, barbiturates, or narcotics: Potentiation of orthostatic hypotension may occur.
Antidiabetic drugs (oral agents and insulin): Dosage adjustment of the antidiabetic drug may be required.
Other antihypertensive drugs: Additive effect or potentiation.
Cholestyramine and colestipol resins: Absorption of hydrochlorothiazide is impaired in the presence of anionic exchange resins. Single doses of either cholestyramine or colestipol resins bind the hydrochlorothiazide and reduce its absorption from the gastrointestinal tract by up to 85% and 43%, respectively.
Corticosteroids, ACTH: Intensified electrolyte depletion, particularly hypokalemia.
Pressor amines (e.g., norepinephrine): Possible decreased response to pressor amines but not sufficient to preclude their use.
Skeletal muscle relaxants, nondepolarizing (e.g., tubocurarine): Possible increased responsiveness to the muscle relaxant.
Lithium: Should not generally be given with diuretics. Diuretic agents reduce the renal clearance of lithium and add a high risk of lithium toxicity. Refer to the package insert for lithium preparations before use of such preparations with Micardis® HCT (telmisartan and hydrochlorothiazide) tablets.
Non-steroidal anti-inflammatory drugs: In some patients, the administration of a non-steroidal anti-inflammatory agent can reduce the diuretic, natriuretic, and antihypertensive effects of loop, potassium-sparing and thiazide diuretics. Therefore, when MICARDIS HCT tablets and non-steroidal anti-inflammatory agents are used concomitantly, the patient should be observed closely to determine if the desired effect of the diuretic is obtained.
Read the Micardis HCT Drug Interactions Center for a complete guide to possible interactions
Last reviewed on RxList: 1/30/2012
This monograph has been modified to include the generic and brand name in many instances.
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