Pyrimethamine and Sulfadiazine
別名: ReBalance, Fansidar (related compound)
### Important Administration Instructions * **Shake the bottle well** before every use to ensure the medication is properly mixed. * **Fasting is required:** Give this medication on an empty stomach, at least **1 hour before** feeding your horse hay or grain. Food can prevent the drug from being absorbed properly. ### What to Expect * **Treatment Crisis:** It is common for your horse's neurologic signs to temporarily **worsen** during the first few days to weeks of treatment. This is usually caused by inflammation as the parasites die off in the nervous system. Do not stop the medication, but do inform your veterinarian. * **Long-term Therapy:** Treatment for EPM is a marathon, not a sprint. Daily treatment is typically required for 3 to 9 months. ### When to Call the Vet Watch closely for signs of drug toxicity, which can affect the bone marrow. Contact your veterinarian immediately if you notice: * Severe depression or lethargy * Unexplained bleeding or bruising (e.g., bleeding gums) * Bloody diarrhea or severe loose stools * Complete loss of appetite
劑量必須由獸醫按你寵物的個別情況決定。切勿在沒有獸醫指導下給予人類藥物或其他寵物的處方藥。
用途
- Treatment of EPM
- Maintaining clinical remission (for horses that have had two relapses)
給藥方式
可能的副作用
- Bone marrow suppression (anemia, leukopenia, neutropenia, thrombocytopenia)
- Reduced appetite or anorexia
- Loose stools or diarrhea
- Urticaria (hives)
- Treatment crisis (temporary worsening of neurologic signs due to parasite die-off)
- CNS effects (seizures, depression - though often secondary to the underlying EPM)
注意事項與禁忌
- Hypersensitivity to pyrimethamine or sulfadiazine
- Horses intended for human consumption
- Use with extreme caution in horses with **preexisting hematologic abnormalities** or those receiving other bone marrow-suppressing drugs. **Pregnancy/Nursing:** Pyrimethamine is teratogenic in rats, and fetal abnormalities have been seen in foals. Sulfas cross the placenta and are distributed into milk. Use in pregnant animals only when benefits clearly outweigh risks. Consider using milk replacer for nursing offspring. **Treatment Crisis:** Neurologic signs may worsen during the first few days to 5 weeks of treatment due to an inflammatory reaction secondary to dying parasites in the CNS.
藥物相互作用
- Antacids: May decrease the bioavailability of sulfonamides if administered concurrently.
- Highly protein-bound drugs (e.g., methotrexate, phenylbutazone, thiazide diuretics, salicylates, probenecid, phenytoin, warfarin): Sulfonamides may displace other highly bound drugs, potentially increasing their free (active) plasma concentrations and risk of toxicity.
- p-Aminobenzoic acid (PABA): Reportedly antagonistic towards the activity of pyrimethamine; clinical significance is unclear.
- Trimethoprim: Use with pyrimethamine/sulfa is not recommended in humans as adverse effects may be additive; however, this combination has been used clinically in horses.
常見問題
Pyrimethamine and Sulfadiazine用於寵物有甚麼用途？
### Important Administration Instructions * **Shake the bottle well** before every use to ensure the medication is properly mixed. * **Fasting is required:** Give this medication on an empty stomach, at least **1 hour before** feeding your horse hay or grain. Food can prevent the drug from being absorbed properly. ### What to Expect * **Treatment Crisis:** It is common for your horse's neurologic signs to temporarily **worsen** during the first few days to weeks of treatment. This is usually caused by inflammation as the parasites die off in the nervous system. Do not stop the medication, but do inform your veterinarian. * **Long-term Therapy:** Treatment for EPM is a marathon, not a sprint. Daily treatment is typically required for 3 to 9 months. ### When to Call the Vet Watch closely for signs of drug toxicity, which can affect the bone marrow. Contact your veterinarian immediately if you notice: * Severe depression or lethargy * Unexplained bleeding or bruising (e.g., bleeding gums) * Bloody diarrhea or severe loose stools * Complete loss of appetite
Pyrimethamine and Sulfadiazine對我的寵物安全嗎？
劑量必須由獸醫按你寵物的個別情況決定。切勿在沒有獸醫指導下給予人類藥物或其他寵物的處方藥。
本文僅供一般健康教育，不能取代專業獸醫意見。如寵物身體不適，請諮詢獸醫。