QUININE SULPHATE

Posology For the treatment and prevention of nocturnal leg cramps:

Adults (including elderly): The recommended dose is 200mg at bedtime. The maximum dose is 300mg. A reduction in frequency of leg cramps may take up to 4 weeks to become apparent. Patients should be monitored closely during the early stages of treatment for adverse effects.

After an initial trial of 4 weeks, treatment should be stopped if there is no benefit. Treatment should be interrupted at approximately three-monthly intervals to reassess the benefit of treatment.

Treatment of chloroquine-resistant malaria:

Adults (including elderly) and children aged 12 years and over: 600mg every 8 hours for 7 days. The dose may depend upon the size of the patient, severity of infection, and evidence of renal or liver disease (when the intervals should be increased), due to a prolonged half-life of the drug.

If quinine resistance is known or suspected on completion of the course additional treatment may be given. This may be one of the following: 1. Doxycycline 200mg daily (as a single dose or in 2 divided doses) for at least 7 days. 2. Clindamycin 300mg four times daily for 5 days.

Children aged 11 years and under: 10mg/kg every 8 hours for 7 days. Method of administration For oral use.

Cinchonism is more common in overdose, but may occur even after normal doses of quinine. In its mild form symptoms include tinnitus, impaired hearing, rashes, headache, nausea and disturbed vision. 9). Visual disorders may include blurred vision, defective colour perception, visual field constriction and total blindness.

Adverse drug reactions are ranked by frequency, the most frequent first, using the following convention: very common (≥ 1/10); common (≥ 1/100 to < 1/10); uncommon (≥ 1/1,000 to < 1/100); rare (≥ 1/10,000 to < 1/1,000); very rare (< 1/10,000), not known (cannot be estimated from the available data).

MedDRA system organ class Adverse Reaction Frequency: not known Blood and lymphatic system disorders Thrombocytopenia, intravascular coagulation, hypoprothrombinaemia, haemoglobinuria, oliguria, haemolytic-uremic syndrome, pancytopenia, haemolysis, agranulocytosis, thrombocytopenic purpura.

Immune system disorders Reports have been received of eczematous dermatitis, oedema, erythema and lichen planus. Hypersensitivity reactions such as angioneurotic oedema, photosensitivity, hot and flushed skin, pruritus, thrombocytopenic purpura and urticaria have also been reported.

Metabolism and nutrition disorders Hypoglycaemia may occur after oral administration although it is more common after parenteral administration. Psychiatric disorders Agitation, confusion. Nervous system disorders Reports of headache, vertigo, excitement, loss of consciousness, coma and death have been received.

Eye disorders Blurred vision, defective colour perception, visual field constriction. Ear and labyrinth disorders Tinnitus, impaired hearing. Cardiac disorders Atrioventricular conduction disturbances, a fall in blood pressure coupled with a feeble pulse.

Prolongation of the QT interval, widening of the QRS complex and T wave flattening has been noted with therapeutic doses. Respiratory, thoracic and mediastinal disorders Bronchospasm, asthma, dyspnoea may occur. Gastrointestinal disorders Nausea, vomiting, diarrhoea, abdominal pain* may occur after long term administration of quinine.

Skin and subcutaneous tissue disorders Flushing, rash, urticaria, eczematous dermatitis, oedema, erythema, lichen planus, pruritus, photosensitivity, Stevens-Johnson syndrome. Musculoskeletal and connective tissue disorders Muscle weakness may occur, aggravation of myasthenia gravis Renal and urinary disorders Renal insufficiency and acute renal failure may be due to an immune mechanism or to circulatory failure, oliguria.

Reproductive system and breast disorders Toxic doses of quinine may induce abortion**, but it is unwise to withhold the drug if less toxic antimalarials are not available. General disorders and administration site conditions Cinchonism*** *May occur after long term administration quinine **Toxic doses of quinine may induce abortion, but it is unwise to withhold the drug if less toxic antimalarials are not available ***More common in overdose, but may occur even after normal doses of quinine.

In its mild form symptoms include tinnitus, impaired hearing, rashes, headache, nausea and disturbed vision. 9). Visual disorders (blurred vision, defective colour perception, visual field constriction and total blindness). Reporting of suspected adverse reactions Reporting suspected adverse reactions after authorisation of the medicinal product is important.

It allows continued monitoring of the benefit/risk balance of the medicinal product. uk/yellowcard or search for MHRA Yellow Card in the Google Play or Apple App Store.

Cinchonism Administration of quinine may give rise to cinchonism, which is generally more severe in overdose, but may also occur in normal therapeutic doses. Patients should be warned not to exceed the prescribed dose, because of the possibility of serious, irreversible side effects in overdose.

Treatment for night cramps should be stopped if symptoms of cinchonism emerge. 9). Hypersensitivity Hypersensitivity to quinine may also occur with symptoms of cinchonism together with urticaria, flushing, pruritus, rash, fever, angioedema, dyspnoea and asthma.

Serious hypersensitivity reactions including Stevens-Johnson syndrome have been reported with quinine. Cardiac disorders Quinine has dose-dependent QT-prolonging effects. Caution is recommended in patients with conditions which predispose to QT-prolongation and in patients with atrioventricular block.

Quinine should be used with caution in patients with atrial fibrillation, other cardiac conduction defects and heart block or other serious heart disease. It may cause hypoprothrombinaemia and enhance the effects of anticoagulants. Glucose-6-Phosphate Dehydrogenase (G-6-PD) Deficiency Quinine has been implicated in precipitating blackwater fever when given for prolonged periods, although in some cases deficiency of glucose-6-phosphate dehydrogenase may have been involved.

Patients with glucose-6-phosphate dehydrogenase deficiency may be at increased risk of haemolysis during quinine therapy and may develop haemolytic anaemia. 6). Treatment with quinine should be monitored in case signs of resistance develop.

8), should be carefully considered relative to the potential benefits. These risks are likely to be of particular concern in the elderly. Quinine should only be considered when cramps are very painful or frequent, when other treatable causes of cramp have been ruled out, and when non-pharmacological measures have not worked.

6). Quinine may cause unpredictable serious and life-threatening thrombocytopenia, which is thought to be an idiosyncratic hypersensitivity reaction. Quinine should not be prescribed or administered to patients who have previously experienced any adverse reaction to quinine, including that in tonic water or other beverages.

Patients should be instructed to stop treatment and consult a physician if signs of thrombocytopenia such as unexplained bruising or bleeding occur. Reduce the dosage (or increase intervals between doses) in renal or hepatic disease.

Patients with rare hereditary problems of galactose intolerance, total lactase deficiency or glucose-galactose malabsorption should not take this medicine. Patients with rare hereditary problems of fructose intolerance, glucose-galactose malabsorption or sucrase-isomaltase insufficiency should not take this medicine.

Sodium content This medicine contains less than 1 mmol sodium (23 mg) per tablet, that is to say essentially ‘sodium-free’.

1. Optic neuritis. Tinnitus. Myasthenia gravis, quinine may cause severe respiratory distress and dysphagia in these patients. Haemolysis or Haemoglobinuria. As quinine has been implicated in precipitating blackwater fever, it is generally contraindicated in patients who have already suffered an attack.