Adverse effects of losartan have been reported to be usually mild and transient, and include dizziness, headache, and dose-related orthostatic hypotension.
Hypotension may occur particularly in patients with volume depletion (for example those who have received high-dose diuretics).
Impaired renal function and, rarely, rash, urticaria, pruritus, angioedema, and raised liver enzyme values may occur.
Hyperkalaemia, myalgia, and arthralgia have been reported.
Losartan appears less likely than ACE inhibitors to cause cough.
Other adverse effects that have been reported with angiotensin II receptor antagonists include respiratory-tract disorders, back pain, gastrointestinal disturbances, fatigue, and neutropenia.
Rhabdomyolysis has been reported rarely.
Hydrochlorothiazide: Body as a whole:
Weakness, chest pain.
Pancreatitis, jaundice (intrahepatic cholestatic jaundice), sialadenitis, cramping, gastric irritation.
Aplastic anemia, agranulocytosis, leukopenia, hemolytic anemia, thrombocytopenia.
Purpura, photosensitivity, urticaria, necrotizing angiitis (vasculitis and cutaneous vasculitis), fever, respiratory distress including pneumonitis and pulmonary edema.
Hyperglycemia, glycosuria, hyperuricemia.
Renal failure, renal dysfunction, interstitial nephritis.
Erythema multiforme including Stevens-Johnson syndrome, exfoliative dermatitis including toxic epidermal necrolysis.
Transient blurred vision, xanthopsia.
Neoplasms benign, malignant and unspecified (incl cysts and polyps):
Non-melanoma skin cancer (Basal cell carcinoma and Squamous cell carcinoma). Based on available data from epidemiological studies, cumulative dose-dependent association between HCTZ and NMSC has been observed.