The following adverse reactions have been observed, but there is not enough systemic collection of data to support an estimate of their frequency.
The most common reactions associated with polythiazide therapy are weakness and dizziness, but seldom require cessation of therapy. Weakness is reported in less than 3% of patients receiving the drug, and dizziness is reported in less than 2% of patients. These can be overcome by reducing the dose or taking measures to improve electrolytic balance.
Other reactions, reported to occur in less than 1% of patients, are:
Gastrointestinal: nausea, gastrointestinal disturbances, reversible cholestatic jaundice, necrotizing angiitis, pancreatitis.
Dermatological: maculopapular skin rash, photosensitivity.
Central Nervous System: vertigo, paresthesia, fatigue, headache.
Cardiovascular: orthostatic hypotension.
Hematological: Leukopenia (neutropenia), agranulocytosis, and aplastic anemia have been reported with the older thiazides but not with the newer compounds such as polythiazide. Purpura (with or without thrombocytopenia) has been reported with polythiazide.
The most common reactions associated with reserpine therapy, dizziness and drowsiness, are reported in less than 2% of patients. Reactions to reserpine are usually reversible and disappear when the drug is discontinued.
Other reactions, occurring in less than 1% of patients on reserpine are:
Gastrointestinal: hypersecretion, nausea, vomiting, diarrhea, anorexia, dry mouth.
Dermatological: rash, pruritus, purpura.
Central Nervous System: depression, nervousness, paradoxical anxiety, nightmares, headache, and rare Parkinsonian syndrome to CNS sensitization manifested by deafness, glaucoma, uveitis, and optic atrophy.
Cardiovascular: angina-like symptoms, arrhythmias particularly when used concurrently with digitalis or quinidine, flushing of the skin, and bradycardia.
EENT: nasal congestion, miosis.
Sexual Difficulties: impotence or decreased libido.