Classifications: antimalarial;
Therapeutic: antimalarial

Prototype: Chloroquine
Pregnancy Category: X


325 mg capsules


Inhibits protein synthesis and depresses many enzyme systems in malaria parasite. Has schizonticidal action and is gametocidal with Plasmodium vivax and Plasmodium malariae but not Plasmodium falciparum. Resembles salicylates in analgesic and antipyretic properties and exerts curare-like skeletal muscle relaxant effect. Also has oxytocic action and hypoprothrombinemic effect. Qualitatively similar to quinidine in cardiovascular effects. Generally replaced by less toxic and more effective agents in treatment of malaria.

Therapeutic Effect

Effective against Plasmodium vivax and Plasmodium malariae but not Plasmodium falciparum. Generally replaced by less toxic and more effective agents in treatment of malaria.


Chloroquine-resistant falciparum malaria and in combination with other antimalarials for radical cure of relapsing vivax malaria; also relief of nocturnal recumbency leg cramps.


Hypersensitivity to quinine; tinnitus, optic neuritis; myasthenia gravis; G6PD deficiency; pregnancy (category X).

Cautious Use

Cardiac arrhythmias. Same precautions as for quinidine sulfate when used in patients with cardiovascular conditions.

Route & Dosage

Acute Malaria
Adult: PO 650 mg q8h for 3 d
Child: PO 25 mg/kg/d in three divided doses q8h for 3 d

Malaria Chemoprophylaxis
Adult: PO 325 mg b.i.d. for 6 wk

Nocturnal Leg Cramps
Adult: PO 260–300 mg h.s.


  • Give with or after meals or a snack to minimize gastric irritation. Quinine has potent local irritant effect on gastric mucosa. Do not crush capsule; drug is not only irritating but also extremely bitter.
  • Store in tight, light-resistant containers.

Adverse Effects (≥1%)

Body as a Whole: Cinchonism (tinnitus, decreased auditory acuity, dizziness, vertigo, headache, visual impairment, nausea, vomiting, diarrhea, fever); hypersensitivity (cutaneous flushing, visual impairment, pruritus, skin rash, fever, gastric distress, dyspnea, tinnitus); hypothermia, coma. CNS: Confusion, excitement, apprehension, syncope, delirium, convulsions, blackwater fever (extensive intravascular hemolysis with renal failure), death. CV: Angina, hypotension, tachycardia, cardiovascular collapse. Hematologic: Leukopenia, thrombocytopenia, agranulocytosis, hypoprothrombinemia, hemolytic anemia. Respiratory: Decreased respiration.

Diagnostic Test Interference

Quinine may interfere with determinations of urinary catecholamines (Sobel and Henry modification procedure) and urinary steroids (17-hydroxycorticosteroids) (modification of Reddy, Jenkins, Thorn method).


Drug: May increase digoxin levels; anticholinergic agents add to vagolytic effects; cholinergic agents may antagonize cardiac effects; anticonvulsants, barbiturates, rifampin increase the metabolism of quinine, thus decreasing its efficacy; carbonic anhydrase inhibitors, sodium bicarbonate, chronic antacids decrease renal elimination of quinine, thus increasing its toxicity; warfarin may increase hypoprothrombinemic effects. Amantadine, carbamazepine, phenobarbital levels may be increased. Food: Grapefruit juice (>1 qt/d) may increase plasma concentrations and adverse effects.


Absorption: Well from GI tract. Peak: 1–3 h. Duration: 6–8 h. Distribution: Widely distributed to most body tissues except the brain; crosses placenta; distributed into breast milk. Metabolism: In liver. Elimination: >95% in urine, <5% in feces. Half-Life: 8–21 h.

Nursing Implications

Assessment & Drug Effects

  • Be alert for S&S of rising plasma concentration of quinine marked by tinnitus and hearing impairment, which usually do not occur until concentration is 10 mcg/mL or more.
  • Follow the same precautions with quinine as are used with quinidine in patients with atrial fibrillation; quinine may produce cardiotoxicity in these patients.

Patient & Family Education

  • Learn possible adverse reactions and report onset of any unusual symptom promptly to physician.

Common adverse effects in italic, life-threatening effects underlined; generic names in bold; classifications in SMALL CAPS; Canadian drug name; Prototype drug

© 2006-2022 medpill.info Last Updated On: 11/16/2022 (0)
Wait 20 seconds...!!!