Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice.
Losartan potassium-hydrochlorothiazide has been evaluated for safety in 858 patients treated for essential hypertension and 3889 patients treated for hypertension and left ventricular hypertrophy. Most adverse reactions have been mild and transient in nature and have not required discontinuation of therapy. In controlled clinical trials, discontinuation of therapy due to clinical adverse events was required in only 2.8% and 2.3% of patients treated with the combination and placebo, respectively.
In these double-blind controlled clinical trials, adverse reactions occurring in greater than 2% of subjects treated with losartan-hydrochlorothiazide and at a greater rate than placebo were: back pain (2.1% vs 0.6%), dizziness (5.7% vs 2.9%), and upper respiratory infection (6.1% vs 4.6%).
The following additional adverse reactions have been reported in clinical trials with losartan potassium and hydrochlorothiazide tablets and/or the individual components:
Blood and the lymphatic system disorders: Anemia, aplastic anemia, hemolytic anemia, leukopenia, agranulocytosis.
Metabolism and nutrition disorders: Anorexia, hyperglycemia, hyperuricemia, electrolyte imbalance including hyponatremia and hypokalemia.
Psychiatric disorders: Insomnia, restlessness.
Nervous system disorders: Dysgeusia, headache, migraine, paraesthesias.
Eye disorders: Xanthopsia, transient blurred vision.
Cardiac disorders: Palpitation, tachycardia.
Vascular disorders: Dose-related orthostatic effects, necrotizing angiitis (vasculitis, cutaneous vasculitis).
Respiratory, thoracic and mediastinal disorders: Nasal congestion, pharyngitis, sinus disorder, respiratory distress (including pneumonitis and pulmonary edema).
Gastrointestinal disorders: Dyspepsia, abdominal pain, gastric irritation, cramping, diarrhea, constipation, nausea, vomiting, pancreatitis, sialoadenitis.
Hepato-biliary disorders: Jaundice (intrahepatic cholestatic jaundice).
Skin and subcutaneous tissue disorders: Rash, pruritus, purpura, toxic epidermal necrolysis, urticaria, photosensitivity, cutaneous lupus erythematosus.
Musculoskeletal and connective tissue disorders: Muscle cramps, muscle spasm, myalgia, arthralgia.
Renal and urinary disorders: Glycosuria, renal dysfunction, interstitial nephritis, renal failure.
Reproductive system and breast disorders: Erectile dysfunction/impotence.
General disorders and administration site conditions: Chest pain, edema/swelling, malaise, fever, weakness.
Investigations: Liver function abnormalities.
Cough
Persistent dry cough has been associated with ACE-inhibitor use and in practice can be a cause of discontinuation of ACE-inhibitor therapy. Two prospective, parallel-group, double-blind, randomized, controlled trials were conducted to assess the effects of losartan on the incidence of cough in hypertensive patients who had experienced cough while receiving ACE-inhibitor therapy. Patients who had typical ACE-inhibitor cough when challenged with lisinopril, whose cough disappeared on placebo, were randomized to losartan 50 mg, lisinopril 20 mg, or either placebo (one study, n = 97) or 25 mg hydrochlorothiazide (n = 135). The double-blind treatment period lasted up to 8 weeks. The incidence of cough is shown in Table 1 below.
Table 1:Study 1 Demographics = (89% Caucasian, 64% female) | HCTZ | Losartan | Lisinopril |
Cough | 25% | 17% | 69% |
Study 2 Demographics = (90% Caucasian, 51% female) | Placebo | Losartan | Lisinopril |
Cough | 35% | 29% | 62% |
These studies demonstrate that the incidence of cough associated with losartan therapy, in a population that all had cough associated with ACE-inhibitor therapy, is similar to that associated with hydrochlorothiazide or placebo therapy.
Cases of cough, including positive re-challenges, have been reported with the use of losartan in postmarketing experience.