QUINI 300MG TABLET

Indications

• Severe falciparum malaria
• Chloroquine-resistant malaria
• Malaria prophylaxis in high-risk areas

Dosage

Children: Child (body-weight 45 kg and above): Loading dose 20 mg

Adults: Loading dose: 20 mg/kg (max. 1.4 g) infused over 4 hours. Maintenance: 10 mg/kg every 8 hours (max. per dose 700 mg). For non-falciparum malaria, 600 mg every 8 hours for 5–7 days, in combination with doxycycline or clindamycin.

Mechanism of action

Quinine and related antimalarial drugs are theorized to be toxic to malaria parasites by interfering with their ability to digest hemoglobin. This leads to starvation of the parasite and accumulation of toxic levels of partially degraded hemoglobin. Quinine acts as a blood schizonticide and has been shown to inhibit heme polymerase, resulting in increased levels of cytotoxic heme within the parasite.

Pharmacodynamics

Quinine is particularly effective against chloroquine-resistant strains of Plasmodium falciparum. It acts as a blood schizonticide and possesses gametocytocidal activity against Plasmodium vivax and Plasmodium malariae. It is a weak base and becomes concentrated in the food vacuoles of the parasite, which enhances its antimalarial efficacy. Due to its side effects and toxicity, its use is generally reserved for severe cases of malaria.

Pharmacokinetics

Quinine is administered intravenously or orally, with a half-life that can vary based on the route of administration and the patient's renal function. Peak plasma concentrations are typically achieved within 1 to 3 hours of intravenous administration. It is metabolized in the liver and excreted primarily through urine. Dosing must be adjusted in cases of renal impairment to avoid toxicity.

Adverse effects

• alopecia
• angioedema
• bone marrow disorders
• choleostasis
• constipation
• diarrhoea
• fever
• gastric disorders
• megaloblastic anaemia
• oral disorders
• skin reactions
• vasculitis

Interactions

• quinine + digoxin: Moderate (increases concentration)
• hiv-protease inhibitors + quinine: Unknown (affects exposure)
• cimetidine + quinine: Unknown (increases exposure)
• rifampicin + quinine: Unknown (decreases exposure)

Precautions

• history of seizures-avoid large loading doses
• predisposition to folate deficiency

Pregnancy

Benefit of prophylaxis in malaria outweighs risk. Adequate folate supplements should be given to the mother.

Breast-feeding

Quinine is excreted in breast milk, caution is advised.

Storage

Store in a cool, dry place. Protect from light.

Formulations

• Quinine hydrochloride
• Quinine dihydrochloride
• Quinine sulfate

Indications

• Nutritional supplementation
• Detoxification support
• Support in certain metabolic disorders

Dosage

Children: Refer to established guidelines for specific dosing based on clinical context and individual needs.

Adults: Refer to established guidelines for specific dosing based on clinical context and individual needs.

Mechanism of action

Sulphate acts as a sulfate donor in metabolic reactions, facilitating the sulfation of various compounds. This process is crucial for the metabolism of drugs, hormones, and neurotransmitters, enhancing their solubility and excretion. The sulfation pathway is essential for the detoxification of xenobiotics and the regulation of biological activity in numerous physiological processes.

Pharmacodynamics

Sulphate is involved in several biological functions, including the maintenance of cellular homeostasis and the modulation of cellular signaling pathways. It contributes to the structural integrity of glycosaminoglycans, which are essential components of connective tissues. Sulphate also plays a role in the regulation of extracellular matrix components, influencing cell signaling and tissue repair processes.

Pharmacokinetics

Sulphate is absorbed in the gastrointestinal tract and is distributed throughout the body via the bloodstream. It is primarily excreted by the kidneys, with renal clearance being the main route of elimination. The half-life of sulphate in the body can vary depending on physiological conditions and dietary intake. In cases of deficiency, supplementation may be necessary, and levels can be monitored through serum measurements.

Contra-indications

• Hypersensitivity to sulphate compounds
• Severe renal impairment
• Active gastrointestinal bleeding

Adverse effects

• Nausea
• Vomiting
• Diarrhea
• Skin rash
• Hypotension
• Allergic reactions

Interactions

• May interact with anticoagulants, increasing the risk of bleeding
• Potential interaction with diuretics, leading to electrolyte imbalances
• Use with caution in combination with other nephrotoxic agents

Precautions

• Use with caution in patients with a history of gastrointestinal disorders
• Monitor renal function in patients with pre-existing kidney disease
• Evaluate for potential drug interactions prior to prescribing

Pregnancy

Not enough data on safety in pregnancy. Use only if clearly needed and benefits outweigh risks.

Breast-feeding

Limited data available. Use with caution and monitor infant for adverse effects.

Storage

Store at room temperature, away from light and moisture. Keep out of reach of children.

Formulations

• Oral tablets
• Intravenous solution

Mechanism of action

The theorized mechanism of action for quinine and related anti-malarial drugs is that these drugs are toxic to the malaria parasite. Specifically, the drugs interfere with the parasite's ability to break down and digest hemoglobin. Consequently, the parasite starves and/or builds up toxic levels of partially degraded hemoglobin in itself. Quinine has a local anesthetic action and analgesic, antipyretic, and oxytocic effects. Quinine also has cardiovascular effects similar to those of quinidine.

Pharmacodynamics

Quinine is used parenterally to treat life-threatening infections caused by chloroquine-resistant Plasmodium falciparum malaria. Quinine acts as a blood schizonticide although it also has gametocytocidal activity against P. vivax and P. malariae. Because it is a weak base, it is concentrated in the food vacuoles of P. falciparum. It is thought to act by inhibiting heme polymerase, thereby allowing accumulation of its cytotoxic substrate, heme. As a schizonticidal drug, it is less effective and more toxic than chloroquine. However, it has a special place in the management of severe falciparum malaria in areas with known resistance to chloroquine.