Jasoquin300 mg

Jasoquin is an antimalarial agent (cinchona alkaloid) with the following indications:

Established / FDA-Approved Use

• Uncomplicated chloroquine-resistant Plasmodium falciparum malaria: Jasoquin is indicated for treatment, but it is always used in combination with a second antimalarial or antibiotic (such as doxycycline, tetracycline, or clindamycin) to shorten the duration of therapy and reduce the risk of recrudescence and resistance.

Not Recommended / Discouraged Use

• Nocturnal leg cramps: Jasoquin was historically used off-label for leg cramps, but this use is now strongly discouraged due to a boxed warning for serious, life-threatening hematologic reactions (see Precautions and Warnings). Jasoquin should not be prescribed or used for leg cramps.

Important: Jasoquin is not used for malaria prophylaxis (prevention) and is not effective as monotherapy for falciparum malaria in most regions due to resistance concerns.

Each tablet/capsule contains Quinine Sulfate as the active ingredient, typically supplied in strengths such as 324 mg (equivalent to approximately 260 mg of quinine base). Strength and available presentations may vary by manufacturer and market; refer to the specific product label for exact composition.

Jasoquin is the sulfate salt of quinine, a naturally occurring cinchona alkaloid originally derived from the bark of the Cinchona tree. It is one of the oldest known antimalarial compounds and remains clinically important for treating chloroquine-resistant strains of Plasmodium falciparum.

Jasoquin acts primarily against the erythrocytic (blood) stage of the malaria parasite and is administered orally, generally as part of a combination regimen with a second antimalarial or antibiotic agent.

Jasoquin belongs to the therapeutic class of Antimalarial agents, specifically the cinchona alkaloid class of blood schizonticides.

Quinine Sulfate is a blood schizonticide active against the erythrocytic stages of Plasmodium species, particularly P. falciparum. Its precise mechanism is not completely elucidated, but it is believed to act by concentrating within the parasite's acidic digestive (food) vacuole, where it interferes with the parasite's ability to detoxify heme released during hemoglobin digestion. Accumulation of free heme is toxic to the parasite, leading to its death.

Quinine Sulfate also has quinidine-like electrophysiological effects on the heart (it is structurally related to the antiarrhythmic quinidine), which underlies its potential for QT-interval prolongation and cardiac toxicity at higher doses.

After oral administration, Quinine Sulfate is well absorbed, extensively metabolized in the liver (primarily via CYP3A4), and excreted mainly in urine as metabolites. It is also a potent inhibitor of the CYP2D6 enzyme.

• Jasoquin should be taken orally, generally with food or milk to reduce gastrointestinal upset.
• Swallow tablets/capsules whole with a full glass of water; do not crush or chew unless the product is specifically formulated to allow this.
• Take doses at evenly spaced intervals (approximately every 8 hours) to maintain effective blood levels.
• Complete the entire prescribed course and the full course of any partner drug (e.g. doxycycline, clindamycin), even if symptoms improve before the course ends.
• If a dose is missed, take it as soon as remembered unless it is almost time for the next dose; do not double the dose.

Jasoquin has several clinically significant drug interactions:

• QT-prolonging drugs (e.g. certain antiarrhythmics, some antipsychotics, other antimalarials such as mefloquine or halofantrine): Concurrent use with Jasoquin increases the risk of additive QT prolongation and life-threatening ventricular arrhythmias (torsades de pointes); concurrent use is contraindicated (see Contraindications).
• Mefloquine: Should not be given concurrently or shortly after Jasoquin due to increased risk of cardiotoxicity and seizures.
• Digoxin: Jasoquin can increase serum digoxin concentrations (similar to quinidine), raising the risk of digoxin toxicity; monitoring of digoxin levels is advised.
• CYP3A4 inhibitors (e.g. ketoconazole, certain macrolides): May increase Jasoquin plasma levels and toxicity risk.
• CYP3A4 inducers (e.g. rifampin, phenytoin, carbamazepine): May reduce Jasoquin plasma levels and therapeutic effectiveness.
• CYP2D6 substrates (e.g. certain beta-blockers, flecainide): Jasoquin is a potent CYP2D6 inhibitor and may increase levels of drugs metabolized by this enzyme.
• Warfarin and other anticoagulants: Jasoquin may potentiate anticoagulant effects; monitor coagulation parameters.
• Insulin/oral hypoglycemics: Jasoquin can stimulate insulin release and cause hypoglycemia; additive hypoglycemic effects are possible.

Common (Cinchonism)

Dose-related "cinchonism" is common with Jasoquin and includes: tinnitus, headache, nausea, vomiting, abdominal discomfort, and mild visual disturbances. These effects are usually reversible with dose reduction or discontinuation.

Serious/Boxed Warning Effects

• Thrombocytopenia and hemolytic uremic syndrome/thrombotic thrombocytopenic purpura (HUS/TTP): Rare but serious and potentially life-threatening; can occur with even a single dose in sensitized individuals.
• Hemolytic anemia, especially in patients with G6PD deficiency.
• Hypoglycemia, due to stimulation of insulin release; more pronounced in pregnant women and those with severe malaria.
• Cardiac arrhythmias, including QT prolongation, particularly with rapid intravenous administration or overdose.
• Hepatotoxicity (uncommon).
• Hypersensitivity reactions including rash, pruritus, and rarely anaphylaxis.

Patients should seek immediate medical attention for unusual bruising/bleeding, dark urine, decreased urination, severe dizziness, palpitations, or signs of allergic reaction.

Pregnancy: Jasoquin should be used in pregnancy only if clearly needed and if the potential benefit justifies the potential risk to the fetus, under close physician supervision. Untreated falciparum malaria in pregnancy carries substantial risk to both mother and fetus, so treatment is generally recommended when indicated; however, pregnant patients are at increased risk of Jasoquin-associated hypoglycemia and require close monitoring. Consult a physician before use in pregnancy.

Lactation: Jasoquin is excreted into breast milk in small amounts. It should be used with caution during breastfeeding, and only under medical supervision, weighing the benefit of treating the mother's malaria against any potential risk to the infant.

Boxed Warning

Serious and life-threatening hematologic reactions, including thrombocytopenia and hemolytic uremic syndrome/thrombotic thrombocytopenic purpura, have been reported with use of Jasoquin, particularly when used off-label for nocturnal leg cramps. Jasoquin should not be used to treat or prevent leg cramps.

Other Precautions

• Cardiac monitoring: Because Jasoquin can prolong the QT interval, ECG monitoring may be warranted in patients with underlying cardiac disease, electrolyte disturbances, or when other QT-prolonging drugs cannot be avoided.
• G6PD deficiency: Use is contraindicated; test if deficiency is suspected and not previously documented.
• Hypoglycemia: Monitor blood glucose, especially in pregnant women, young children, and patients with severe malaria.
• Cinchonism: Monitor for tinnitus, headache, and visual disturbances; consider dose reduction if symptoms are bothersome.
• Use with caution in patients with hepatic or renal impairment, and in the elderly.
• Jasoquin must be taken exactly as prescribed by a physician; do not stop, extend, skip doses, or share this medicine with others without medical advice.

Overdose of Jasoquin is potentially life-threatening and can cause severe cinchonism, cardiac arrhythmias (including QT prolongation and cardiac arrest), profound hypotension, visual disturbances or blindness, deafness, seizures, and respiratory failure.

If overdose is suspected, seek immediate medical attention or contact emergency services/a poison control center right away. Do not attempt to manage a suspected overdose at home; treatment requires hospital-based supportive and monitored care.

Store at room temperature (below 30°C), away from light and moisture. Keep out of reach of children.

• Renal impairment: Use Jasoquin with caution; dose reduction and monitoring for accumulation-related toxicity may be needed in significant renal impairment.
• Hepatic impairment: Use with caution, as Jasoquin is hepatically metabolized; dose adjustment may be warranted in significant impairment.
• Elderly: May be more susceptible to cardiac and cinchonism-related adverse effects; use with caution and monitor closely.
• G6PD-deficient patients: Contraindicated due to risk of severe hemolysis (see Contraindications).
• Pregnant women: See Pregnancy and Lactation; increased risk of hypoglycemia requires close monitoring.
• Children: Weight-based dosing is used for malaria treatment; Jasoquin should not be used for leg cramps in any age group.

For uncomplicated chloroquine-resistant P. falciparum malaria, Jasoquin is typically given for 3 to 7 days, depending on the geographic region where the infection was acquired (e.g. longer courses for infections acquired in Southeast Asia), always in combination with a partner drug (doxycycline, tetracycline, or clindamycin) given for a similar or extended duration as directed by the physician. Jasoquin should not be used long-term or intermittently for non-malarial indications such as leg cramps.

Quinine Sulfate is classified as an Antimalarial agent belonging to the cinchona alkaloid class, with structural and electrophysiological similarity to the Class IA antiarrhythmic quinidine.

Quinine Sulfate exerts its antimalarial effect by accumulating in the acidic digestive vacuole of the intraerythrocytic malaria parasite, where it inhibits the parasite's ability to detoxify heme (a toxic byproduct of hemoglobin digestion) into inert hemozoin. The resulting accumulation of free heme is toxic to the parasite, leading to parasite death. Quinine Sulfate acts on the erythrocytic (blood) stages of Plasmodium and has no significant activity against liver-stage parasites.

C

Jasoquin is used in children for treatment of uncomplicated chloroquine-resistant P. falciparum malaria at a weight-based dose of approximately 8.3 mg/kg (salt) orally every 8 hours, in combination with clindamycin (preferred over doxycycline/tetracycline in younger children), for 3–7 days depending on region of infection acquisition.

Safety and efficacy of Jasoquin for indications other than malaria (e.g. leg cramps) have not been established in children, and such use is not recommended. Children should be monitored closely for cinchonism, hypoglycemia, and cardiac effects during treatment.