Quinine Sulfate (quinine sulfate)

Dosage of quinine sulfate is expressed in terms of the salt.

The only FDA-approved preparations of quinine sulfate currently commercially available in the US are capsules containing 324 mg of quinine sulfate (Qualaquin(R); generic); the drug was previously available in the US as capsules containing 325 mg. This difference in quinine sulfate preparations may result in minor disparities between some published dosage recommendations that were based on the previously available 325-mg capsules and dosage recommendations for the currently available 324-mg capsules.

Quinine sulfate is administered orally.

Although quinine has been administered by slow IV infusion as quinine dihydrochloride, a parenteral preparation of the drug is no longer is available for use in the US, either commercially or from the US Centers for Disease Control and Prevention (CDC). When parenteral antimalarial therapy is indicated, IV quinidine gluconate should be used. (See Quinidine in 24:04.04.04.)

Quinine sulfate should be administered with food to minimize possible GI irritation.

Patients should be advised to take quinine sulfate exactly as prescribed and to contact their clinicians if they have questions regarding the prescribed dosage regimen, including missed doses. If a patient misses a dose, they should be advised not to double the next dose; if more than 4 hours have elapsed following a missed dose, the patient should not take the missed dose and should take the next dose as previously scheduled.

No dosing information is available for this tab.

No dosing information is available for this tab.

There is no enhanced messaging for this drug.

There are no contraindication interactions for this drug.

There are no severe interactions for this drug.

There are no moderate interactions for this drug.

There is no enhanced messaging for this drug.

There are no contraindication contraindications for this drug.

There are no severe contraindications for this drug.

There are no moderate contraindications for this drug.

There is no enhanced messaging for this drug.

There are no severe adverse reactions for this drug.

There are no less severe adverse reactions for this drug.

No enhanced messaging available.

No enhanced messaging available.

The manufacturers state that quinine should be used during pregnancy only if the potential benefits justify the potential risks to the fetus.

The CDC recommends oral quinine sulfate and clindamycin as a regimen of choice for the treatment of uncomplicated chloroquine-resistant P. falciparum in pregnant women. (See Treatment of Uncomplicated Malaria under Uses: Malaria.)

Although published data on more than 1000 quinine pregnancy exposures (majority of exposures occurred after the first trimester) did not show an increased risk of teratogenic effects compared with the background rate in the general population, there are few well-controlled studies to date evaluating quinine in pregnant women.

Hypoglycemia, due to increased pancreatic secretion of insulin, has been associated with quinine use, especially in pregnant women. In one study in women in the third trimester of pregnancy with severe P. falciparum malaria who received IV quinine dihydrochloride (no longer available in the US either commercially or from the Parasitic Diseases Drug Service of the CDC) in the recommended dosage, there was no apparent adverse effect on the fetuses; however, these women appeared to be particularly susceptible to the hypoglycemic effects of quinine.

There is no evidence to date that quinine causes uterine contractions at dosages recommended for the treatment of malaria. However, doses severalfold higher than those used to treat malaria may stimulate the pregnant uterus.

Quinine crosses the placenta resulting in measurable blood concentrations in the fetus. In a small number of women who delivered live infants 1-6 days after starting quinine therapy, placental cord plasma quinine concentrations were 1-4.6 mg/L (mean: 2.4 mg/L) and the mean ratio of cord plasma to maternal plasma quinine concentrations ranged from 0.18-0.46 mg/L (within 1 standard deviation). Such placental cord plasma quinine concentrations may not result in therapeutic fetal plasma quinine concentrations. If congenital malaria is suspected, the infant should be evaluated after delivery and treated with antimalarial agents if appropriate.

Animal developmental studies have been conducted in multiple species using subcutaneous or IM quinine dosages similar to the maximum recommended human dosage (MRHD) of 32 mg/kg daily based on body surface area (BSA) comparisons. Teratogenic and fetotoxic effects were observed in rabbits (e.g., death in utero, degenerated auditory nerve and spiral ganglion, CNS anomalies (anencephaly, microcephaly)), dogs (e.g., death in utero), and guinea pigs (e.g., hemorrhage, mitochondrial change in cochlea). There were no teratogenic effects observed in rats or monkeys given the drug at dosages corresponding to 1 or 2 times the MRHD, respectively. In a pre- postnatal study in rats, oral quinine sulfate at a dosage corresponding to approximately 0.1 times the MRHD based on BSA comparison resulted in offspring with impaired growth, lower body weights at birth and during the lactation period, and delayed physical development of teeth eruption and eye opening during the lactation period.

Deafness and optic nerve hypoplasia have been reported rarely in children exposed in utero when the mother received high-dose quinine therapy during pregnancy. Quinine reportedly has caused congenital malformations in humans when used in large doses (up to 30 g) for attempted abortion. Deafness related to auditory nerve hypoplasia was reported in about half of these cases; limb anomalies, visceral defects, and visual changes have also been reported. No clinically important difference in the rate of stillbirths at greater than 28 weeks of gestation was reported in women in Thailand with P. falciparum malaria treated with 10 mg/kg of quinine orally 3 times daily for 7 days during various stages of pregnancy (1.6%) compared with the rate of stillbirths reported in women without malaria or treatment with antimalarial agents during pregnancy (1.8%). In addition, the overall rate of congenital malformations (1.4%) was similar in pregnant women who received quinine compared with the rate observed in those who did not receive the drug (1.7%), and the rate of spontaneous abortion was higher in the women without malaria or treatment with antimalarial agents during pregnancy (10.9%) than in women treated with quinine during gestation (3.5%). There was no increased risk of structural birth defects reported in an epidemiologic survey that included 104 mother-child pairs exposed to quinine during the initial 4 months of gestation.

Malaria infection in pregnant women is associated with high risks of both maternal and perinatal morbidity and mortality. Pregnant women with P. falciparum malaria have an increased incidence of fetal loss (e.g., spontaneous abortion, stillbirth), preterm labor and delivery, intrauterine growth retardation, low birth weight, and maternal death. Therefore, prompt treatment of malaria during pregnancy is important.

Although quinine generally is considered compatible with breast-feeding, the risks and benefits to the infant and mother should be assessed and the drug should be used with caution in nursing women.

Data to date are limited regarding the safety of quinine in breast-fed infants. In a single study of nursing women who received 10 mg/kg of quinine orally every 8 hours for 1-10 days, there was no evidence of infant toxicity. Estimates from this study indicate that breast-fed infants are exposed to less than 2-3 mg of quinine base (less than 0.4% of the maternal dose) daily through breast milk. (See Pharmacokinetics: Distribution.)

Plasma quinine concentrations may not be therapeutic in infants of nursing mothers receiving quinine. If malaria is suspected in the infant, appropriate evaluation and treatment should be provided.

No enhanced messaging available.