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Pharmacologic class: Cinchona alkaloid
Therapeutic class: Antimalarial
Pregnancy risk category C
Unknown. Thought to interfere with DNA synthesis by increasing pH in intracellular organelles of susceptible parasites.
Capsules: 324 mg
Indications and dosages
➣ Uncomplicated Plasmodium falciparum malaria
Adults and children age 16 and older: 648 mg (two capsules) P.O. q 8 hours for 7 days
• Severe chronic renal impairment
• Hypersensitivity to drug (including but not limited to thrombocytopenia, idiopathic thrombocytopenia purpura, thrombocytopenic purpura, hemolytic uremic syndrome, blackwater fever), mefloquine, quinidine
• G6PD deficiency
• Optic neuritis
• Prolonged QT interval
• Myasthenia gravis
Use cautiously in:
• renal or hepatic impairment
• concurrent use of digoxin and drugs known to prolong QT interval, including Class IA antiarrhythmics (such as disopyramide, procainamide, quinidine) and Class III antiarrhythmics (such as amiodarone, dofetilide, sotalol)
• concurrent use of antacids, rifampin, ritonavir, neuromuscular blockers, macrolide anti-infectives, CYP3A4 substrates, including astemizole, cisapride, terfenadine (not available in U.S.), pimozide, halofantrine, quinidine (avoid use)
• pregnant or breastfeeding patients.
• children younger than age 16 (safety and efficacy of capsules not established).
• Give with or without food.
CNS: headache, vertigo, syncope, apprehension, restlessness, excitement, confusion, delirium, dizziness, seizures
CV: angina, vasculitis, cardiac rhythm or conduction disturbances
EENT: diplopia, amblyopia, blurred vision, scotoma, abnormal color perception, photophobia, night blindness, mydriasis, optic atrophy, hearing loss, tinnitus
GI: nausea, vomiting, diarrhea, abdominal cramps, epigastric pain, dysphagia
GU: hemolytic uremic syndrome Hematologic: hemolytic anemia, hypoprothrombinemia, acute hemolysis, thrombocytopenic purpura, agranulocytosis
Metabolic: hypothermia, hypoglycemia
Skin: rash, pruritus, photosensitivity, flushing, diaphoresis
Other: cinchonism, facial edema, hypersensitivity reactions including fever and hemolytic uremic syndrome
Drug-drug. Aminophylline, theophylline: increased quinine mean area under the curve (AUC) and Cmax.
Antacids: delayed or decreased quinine absorption
Atorvastatin, other HMG-CoA reductase inhibitors that are CYP3A4 substrates: increased risk of myopathy
Cimetidine: decreased metabolism and increased effects of quinine
Class IA, Class III antiarrhythmics: increased risk of ECG abnormalities, including prolonged QT interval
CYP3A4 inducers (such as carbamazepine, phenobarbital, phenytoin): decreased quinine plasma concentration and increased carbamazepine, phenobarbital, and phenytoin AUC and Cmax
CYP3A4 inducers or inhibitors, CYP3A4 and CYP2D6 substrates: decreased efficacy and increased adverse effects of these drugs
Digoxin: increased digoxin blood level
Other antimalarials including halofantrine, mefloquine: increased risk of seizures, ECG abnormalities, and cardiac arrest
Neuromuscular blockers: increased effects of these drugs, leading to respiratory difficulty
Rifampin: increased metabolism and decreased effects of quinine
Ritonavir: increased quinine mean AUC, Cmax, and elimination half-life
Succinylcholine: delayed succinylcholine metabolism
Tetracycline: increased quinine mean plasma concentration
Urinary alkalizers (such as acetazol-amide, sodium bicarbonate): increased quinine blood level and risk of toxicity
Warfarin: increased warfarin effects, increased risk of bleeding
Drug-diagnostic tests. Urinary 17-ketogenic steroids: elevated levels
Monitor for signs and symptoms of hypersensitivity reaction, including fever and hemolytic uremic syndrome. Discontinue drug if signs or symptoms of hypersensitivity occur.
• Stay alert for signs and symptoms of cinchonism, including tinnitus, headache, nausea, and visual disturbances.
Assess for bleeding tendency, arrhythmias, and hepatotoxicity.
• Monitor CBC, renal and liver function tests, and quinine and glucose levels.
• Tell patient he may take with or without food.
Teach patient to recognize and immediately report signs and symptoms of cinchonism, cardiac arrhythmias, nephrotoxicity, and hepatotoxicity.
Instruct patient to report unusual bleeding or bruising.
• Tell female patient to discuss pregnancy or breastfeeding with prescriber before taking drug.
• As appropriate, review all other significant and life-threatening adverse reactions and interactions, especially those related to the drugs and tests mentioned above.