Pyrimethamine: regimen of use, mechanism of action, indications, contraindications

Release form

Tablets 5, 10 and 25 mg

Mechanism and spectrum of action

An antiprotozoal drug used for the treatment of toxoplasmosis in combination with sulfadiazine, co-trimoxazole, spiramycin or clindamycin in age-related doses.

For the treatment of resistant tropical malaria it is used in combination with sulfadoxine.

Contraindications are

• hypersensitivity,
• metaloblastic B12 deficiency anemia,
• anemia associated with folic acid deficiency.

Application diagram

Prevention against malaria:

• taken orally for adults – 25 mg once a week,
• children 5-10 years old - 12.5 mg once a week.

Prevention begins before entering the outbreak and continues for 4 weeks after leaving.

Treatment is carried out in combination with the above drugs.

Toxoplasmosis:

• taken by adults orally after meals, 25 mg 2 times a day in combination with sulfadimidine (1 g 2 times a day), 2-3 courses for 7-10 days with breaks of 10 days;
• children 10 months-2 years old - pyrimethamine 12.5 mg, sulfadiazine 150 mg/kg body weight per day for 4 doses;
• 2-6 years – pyrimetami 2 mg/kg, then 1 mg/kg per day, sulfadiazine 150 mg/kg per day for 4 doses;
• over 6 years old - pyrimethamine 50 mg/kg per day, then 25 mg/kg per day, sulfadiazine 150 mg/kg body weight per day for 4 doses.

Uveitis:

take pyrimethamine in the first 3 days - 100 mg, then 50 mg per day.

The course lasts 3-6 weeks; if it is necessary to continue treatment, take a 2-week break between courses.

The scientific information provided is general and cannot be used to make a decision about the possibility of using a particular drug.
There are contraindications, consult your doctor.