Dosing and uses of Qualaquin (quinine)
Adult dosage forms and strengths
capsule
- 324mg
Malaria
Uncomplicated (P. falciparum)
- 648 mg PO q8hr x 7 days
Chloroquine -Resistant (P. falciparum)
- 648 mg PO q8hr x 3-7 days with concomitant tetracycline, doxycycline, or clindamycin
Chloroquine-Resistant (P. vivax)
- 648 mg PO q8hr x 3-7 days with concomitant doxycycline (or tetracycline) and PO primaquine
Babesiosis
648 mg PO q8hr x 7 days, with concomitant PO or IV clindamycin
Dosage modifications
Severe, chronic renal impairment: 648 mg PO once, then 324 mg PO q12hr
Hepatic impairment
- Mild or moderate (Child-Pugh A or B): No dosage adjustment required; monitor closely
- Severe (Child-Pugh C): Do not administer
Pediatric dosage forms and strengths
capsule
- 324mg
Malaria
Uncomplicated (P. falciparum)
- 30 mg/kg/day PO divided TID x 3–7 days
- Should not exceed the usual adult PO dosage.
Chloroquine-Resistant (P. falciparum)
- 30 mg/kg/day PO divided TID x3-7 days, with concomitant doxycycline, tetracycline or clindamycin
- Should not exceed the usual adult PO dosage.
Chloroquine-Resistant (P. vivax)
- 30 mg/kg/day PO TID x 3–7 days, with concomitant doxycyline & PO primaquine
- Should not exceed the usual adult PO dosage.
Babesiosis (Off-label)
25 mg/kg/day PO divided TID x7 days, with concomitant oral clindamycin
Qualaquin (quinine) adverse (side) effects
<1%
Flushing of the skin
Anginal symptoms
Fever
Rash
Pruritus
Hypoglycemia
Epigastric pain
Hemolysis in G6PD deficiency
Thrombocytopenia
Hepatitis
Nightblindness
Diplopia
Optic atrophy
Impaired hearing
Hypersensitivity reaction
Frequency not defined
Severe headache
Nausea
Vomiting
Diarrhea
Blurred vision
Tinnituscinchonism (risk of cinchonism is directly related to dose and duration of therapy)
Warnings
Black box warnings
Limited or no benefit for treatment/prevention of nocturnal leg cramps
May cause serious and life-threatening hematologic reactions, including thrombocytopenia and hemolytic uremic syndrome/thrombotic thrombocytopenic purpura (HUS/TTP)
Chronic renal impairment associated with the development of TTP has been reported
Contraindications
Hypersensitivity
G6PD deficiency
Optic neuritis, tinnitus, history of quinine-associated blackwater fever and thrombocytopenic purpura
Pregnancy
Cautions
Reduce parenteral dose by half if >48 hr parenteral treatment required; monitor EKG, BP, glucose with parenteral treatment
FDA warns against unapproved use for leg cramps because of unpredictable serious and life-threatening hematologic reactions including thrombocytopenia and hemolytic-uremic syndrome/thrombotic thrombocytopenic purpura (HUS/TTP)
QT prolongation
- Concentration-dependent prolongation of the PR and QRS interval observed
- At particular risk are patients with underlying structural heart disease and preexisting conduction system abnormalities, elderly patients with sick sinus syndrome, patients with atrial fibrillation with slow ventricular response, patients with myocardial ischemia or patients receiving drugs known to prolong the PR interval (eg, verapamil) or QRS interval (eg, flecainide or quinidine)
Pregnancy and lactation
Pregnancy category: X (first trimester)
Lactation: enters breast milk
Pregnancy categories
A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.
B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.
C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.
D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.
X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.
NA: Information not available.
Pharmacology of Qualaquin (quinine)
Absorption: readily, mainly from upper small intestine
Protein Bound: 70-95%
Metabolism: primarily hepatic
Half-life elimination: children: 6-12 hr; adults: 8-14 hr
Peak Plasma Time: 1-3 hr
Excretion: feces & saliva; urine (<5% as unchanged drug)
Mechanism of action
Unknown; may disrupt Plasmodium DNA transcription/replication
Administration
IV Administration
Was administered by slow IV infusion as the dihydrochloride; however, a parenteral dosage form of the drug no longer is available in the Us