Aralen (Chloroquine) is a 4-aminoquinoline derivative antimalarial drug. This drug has a pronounced and rapid schizontocidal activity. In the process of their development in red blood cells, parasites secrete the degradation product of ferriprotoporphyrin IX, which is a chloroquine receptor. It has not been precisely discovered whether this receptor complex damages the parasite membrane or if there are any other mechanisms, such as DNA synthesis disruption, which lead to the death of malarial plasmodia. The ability of chloroquine to concentrate in red blood cells damaged by parasites provides selective toxicity of the drug in relation to the erythrocyte phase of plasmodium infection.
- Malaria caused by plasmodia sensitive to the drug;
- Prevention of malaria in individuals who have visited endemic areas;
- Diseases of the joints, connective tissue, and skin (as an additional treatment for rheumatoid arthritis, systemic lupus erythematosus, photodermatosis, and porphyria).
Dosage and mode of application
Adults are recommended to start using the drug 1–2 weeks before visiting the endemic area and continue for 4–6 weeks after returning from there. Take 2 tablets (0.5 g) every week on the same day of the week.
The dose for children is determined taking into account body weight (7.6 mg/kg). The method and duration of treatment are the same as for adults.
Adults are prescribed 1 g per one dosage, after 6-8 hours – 500 mg, on the 2nd and 3rd day – 500 mg. The daily dose of the drug is taken for 1 dose.
The initial dose for children is 16 mg/kg at 1 dose, after 6-8 hours – 7.6 mg/kg, on the 2nd and 3rd day – 7.6 mg/kg/day is prescribed.
Adults are prescribed 4 tablets (1.0 g) per day for 2 weeks, then 2 tablets (0.5 g) per day for 2–3 weeks.
For children, the daily dose is prescribed taking into account body weight (16 mg/kg). The method and duration of use are the same as in adults.
Rheumatoid arthritis and systemic lupus erythematosus
Adults are recommended to prescribe 250 mg/day. The therapeutic effect is manifested, as a rule, after 4 weeks of treatment. After reaching the maximum effect, the dose of Aralen can be reduced.
- Pathological changes in the retina;
- Changes in the visual fields of any origin;
- Hypersensitivity to aminoquinoline derivatives.
In the case of prolonged treatment with Aralen in high doses, there may be found side effects such as:
- the organ of vision;
- muscle weakness;
- muscle cramps;
- hearing impairment;
- abdominal pain;
- skin itching;
- hyperpigmentation of the skin and mucous membranes;
- hair loss and grayness;
- decreased blood pressure;
- cardiotoxicity with changes on the ECG.
The simultaneous use of Aralen with phenylbutazone, gold preparations, penicillamine, cytostatics, levamisole is prohibited.
Increased caution requires the simultaneous administration of Aralen with cimetidine, quinine, and other antimalarial drugs, GCS, kaolin, antacids, metronidazole, MAO inhibitors, digitalis drugs, chloroquine, and when immunized with the typhoid fever vaccine.
The main symptoms are collapse (due to the potential cardiotoxicity of the drug), coma and apnea. After the appearance of nausea and vomiting, further overdose symptoms can occur very quickly. Death can occur as a result of heart and respiratory failure or fatal arrhythmias. Possible therapy is indicated gastric lavage, the appointment of activated carbon. Be sure to monitor the functions of the cardiovascular (with ECG monitoring, measuring central venous pressure) and respiratory systems, the level of electrolytes and gases in the blood plasma, and if necessary, correct hypokalemia and acidosis.
With severe intoxication, the following urgent measures are recommended: epinephrine is infused at an initial rate of 0.25 μg/kg/min and gradually increases by 0.25 μg/kg/min until systolic blood pressure is restored to a level of at least 100 mmHg Art. Epinephrine reduces the effects of chloroquine due to inotropic and vasoconstrictor effects.
If cardiac conduction is impaired, intravenous sodium bicarbonate is prescribed at 1-2 mmol/kg every 15 min. With ventricular tachycardia or fibrillation, electro cardioversion is performed. With the exception of life-threatening arrhythmias, other heart rhythm disturbances do not require treatment. The administration of quinidine-like antiarrhythmic drugs should be avoided.
In convulsions – diazepam infusion (2 mg/kg during the first 30 minutes), and then 1-2 mg/kg/day for 2-4 days.
Forced diuresis, hemo- or peritoneal dialysis and metabolic blood transfusion with chloroquine poisoning are ineffective. Due to the very slow elimination of chloroquine from the body, monitoring of patients with an overdose should be continued for several days.