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(Generic versions may still be available.)
Adverse reactions are usually reversible upon reduction of dosage or discontinuation of hydralazine HCI and hydrochlorothiazide. Whenever adverse reactions are moderate or severe, it may be necessary to discontinue the drug.
The following adverse reactions have been observed, but there has not been enough systematic collection of data to support an estimate of their frequency.
Less FrequentDigestive: Constipation, paralytic ileus. Cardiovascular: Hypotension, paradoxical pressor response, and edema. Respiratory: Dyspnea. Neurologic: Peripheral neuritis, evidenced by paresthesia, numbness, and tingling; dizziness; tremors; muscle cramps; psychotic reactions characterized by depression, disorientation, or anxiety. Genitourinary: Difficulty in urination. Hematologic: Blood dyscrasias, consisting of reduction in hemoglobin and red cell count, leukopenia, agranulocytosis, purpura, lymphadenopathy, splenomegaly. Hypersensitive Reactions: Rash, urticaria, pruritus, fever, chills, arthralgia, eosinophilia, and rarely, hepatitis. Other: Nasal congestion, flushing, lacrimation, and conjunctivitis.
The following adverse reactions have been observed but there has not been enough systematic collection of data to support an estimate of their frequency. Consequently the reactions are categorized by organ systems and are listed in decreasing order of severity and not frequency.Digestive: Pancreatitis, jaundice (intrahepatic cholestatic), sialadenitis, vomiting, diarrhea, cramping, nausea, gastric irritation, constipation, anorexia. Cardiovascular: Orthostatic hypotension (may be potentiated by alcohol, barbiturates, or narcotics). Neurologic: Vertigo, dizziness, transient blurred vision, headache, paresthesia, xanthopsia, weakness, and restlessness. Musculoskeletal: Muscle spasm. Hematologic: Aplastic anemia, agranulocytosis, leukopenia, and thrombocytopenia. Metabolic: Hyperglycemia, glycosuria, and hyperuricemia. Hypersensitive Reactions: Necrotizing angitis, Stevens-Johnson syndrome, respiratory distress including pneumonitis and pulmonary edema, purpura, urticaria, rash, photosensitivity.
Read the Apresazide (hydralazine and hydrochlorothiazide) Side Effects Center for a complete guide to possible side effects
MAO inhibitors should be used with caution in patients receiving hydralazine.
When other potent parenteral antihypertensive drugs, such as diazoxide, are used in combination with hydralazine, patients should be continuously observed for several hours for any excessive fall in blood pressure. Profound hypotensive episodes may occur when diazoxide injections and hydralazine are used concomitantly.
Hypokalemia may develop during concomitant use of steroids or ACTH.
Insulin requirements in diabetic patients may be increased, decreased, or unchanged.
Thiazides may decrease arterial responsiveness to norepinephrine, but not enough to preclude effectiveness of the pressor agent for therapeutic use.
Thiazides may increase the responsiveness to tubocurarine.
Lithium renal clearance is reduced by thiazides, increasing the risk of lithium toxicity.
There have been rare reports in the literature of hemolytic anemia occurring with the concomitant use of hydrochlorothiazide and methyldopa.
Drug/Laboratory Test Interactions
Thiazides may decrease serum levels of protein-bound iodine without signs of thyroid disturbance. Hydralazine HCI and hydrochlorothiazide should be discontinued before tests for parathyroid function are made (See General, Hydrochlorothiazide, Calcium excretion).
Last reviewed on RxList: 12/8/2004
This monograph has been modified to include the generic and brand name in many instances.
Additional Apresazide Information
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You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.
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