pyrimethamine

For the treatment of equine protozoal myeloencephalitis (EPM) caused by Sarcocystis neurona.

Do not use in horses intended for human consumption. Federal law restricts this drug to use by or on the order of a licensed veterinarian.

ReBalance®

ReBalance Antiprotozoal Oral Suspension is indicated for the treatment of horses with equine protozoal myeloencephalitis (EPM) caused by Sarcocystis neurona.

ReBalance Antiprotozoal Oral Suspension

Sulfonamides (a specific group of antimicrobial agents) and pyrimethamine are two different antimicrobial agents which inhibit folic acid synthesis at two different sites, in the same synthetic pathway. The combination of a sulfonamide and pyrimethamine is synergistic with the drug combination having an antiprotozoal effect.

ReBalance Antiprotozoal Oral Suspension

The use of ReBalance Antiprotozoal Oral Suspension in contraindicated in horses with known hypersensitivity to sulfonamide drugs or pyrimethamine.

ReBalance Antiprotozoal Oral Suspension

For use in horses only. Do not use in horses intended for human consumption. Not for human use. Keep out of the reach of children.

ReBalance Antiprotozoal Oral Suspension

Seventy-five horses (37 horses in the 1X group, 38 horses in the 2X group) that were treated with test article for at least 90 days were evaluated for adverse reaction. Bone marrow suppression: Anemia: ReBalance Antiprotozoal Oral Suspension administration caused overall anemia (classification of anemia based on HBC, Hgb, and PCV/HCT values in 12% of the observations in the 1X group and 21% of the 2X group. In the 1X group, anemia was noted in in 22%, leukopenia in 19%, neutropenia in 5% and thrombocytopenia in 3% of the cases. In the 2X group, anemia was noted in 58%, leukopenia in 55%, neutropenia in 29% and thrombocytopenia in 5% of the cases. The incidence of bone marrow suppression in the 2X treatment group was two or more times that of the 1X group and the degree of suppression was more serious (mild to severe vs. mild to moderate). because of these blood dyscrasias, test article was interrupted over four times more often in horses treated at the 2X dosage than those treated 1X, Although both groups were off treatment for about the same amount of time (approximately 20% of the treatment period). In some instances of bone marrow suppression, diet was supplemented with folinic acid. GI: Anorexia was observed in two horses in the 1X group and one hose in the 2X group. One horse in the 1X group and one horse in the 2X group were observed to be off feed. Observation of Anorexia and decreased appetite occurred predominately during the first 90 days of the treatment period. Observation of anorexia/decreased appetite in two of the above-referenced cases were due to unrelated illnesses. Loose stools were observed in three horses in the 1X group and five in the 2X group. The majority of these observations occurred in the first thirty days of treatment . Diarrhea was observed in one horse in the 2X group on Day 4 of the study. The appearance of loose stool/diarrhea observations were self-limiting and resolved without treatment or discontinuation of test article. Brief, mild colic was observed in the three cases (one in the 1X group and two in the 2X group). colic was treated conservatively or not at all and resolved without sequelae. Integument: Urticaria was observed in one horse in the 1X group and two horses in the 2X group. One horse was treated topically, two were untreated. All cases resolved without sequelae. Treatment crisis: (marked worsening of the neurological condition) was reported in one horse in the 1X treatment group. Depression/lethargy was observed infrequently occurred during the early part of the study in both groups and was primarily associated with the EPM syndrome. In one case, depression was associated with acute onset of a liver disorder. Seizure: One horse in the 1X treatment group suffered from seizures. Seizure activity may be associated CNS damage from EPM.

ReBalance Antiprotozoal Oral Suspension

Administer orally 20 milligrams sulfadiazine per kilogram body weight and 1 milligram per kilogram pyrimethamine daily or 4 mL oral suspension per 110 lb (50 kg) of body weight once per day.

Oral

Do not use in horses intended for human consumption. Federal law restricts this drug to use by or on the order of a licensed veterinarian.

ReBalance®

ReBalance Antiprotozoal Oral Suspension is to be administered at a dose of 20 mg/kg sulfadiazine and 1 mg/kg pyrimethamine daily or 4 mL of ReBalance Antiprotozoal Oral Suspension per 110 lb. (50 kg) of body weight once per day. The duration of treatment is dependent upon clinical response, but the usual treatment regimen ranges from 90 to 270 days. Administer orally by suitable dosing syringe at least one hour prior to feeding with hay or grain. Insert nozzle of syringe through the interdental space and deposit the dose on the back of the tongue by depressing the plunger. Shake well before use.

ORAL

ReBalance Antiprotozoal Oral Suspension