Primaquine
Also known as: Generic (Sanofi Winthrop)
- **Strict Dosing**: This medication has a very low safety margin when used in cats. Exact adherence to the prescribed dosage is extremely important. **Never** double-up the next dose if a dose was previously missed. - **Administration**: Give the dose with food to reduce the chance of gastrointestinal problems, particularly vomiting. - **Monitoring**: Watch your pet closely for signs of lethargy, pale or discolored gums, or breathing difficulties, and report any abnormalities to your veterinarian immediately.
Dosage must be set by your veterinarian for your specific pet. Never give human medication or another pet’s prescription without veterinary guidance.
What it is used for
- Babesia felis
- Babesia felis
- Babesia felis
How it is given
Possible side effects
- Vomiting (most common in cats)
- Nausea
- Myelosuppression
- Methemoglobinemia
- Hemolysis
Cautions & contraindications
- Known hypersensitivity to primaquine
- Concurrent use of bone marrow suppressant medications
- Patients susceptible to granulocytopenia (e.g., lupus, rheumatoid arthritis)
- Glucose-6-Phosphate Dehydrogenase (G-6-PD) deficiency
- Pregnancy
- Lactation
- > **WARNING**: Primaquine has an extremely narrow therapeutic index in cats. - **Dosing Confusion**: Commercially available human tablets are usually too concentrated for domestic cats. A specialized compounding pharmacy is highly recommended. Prescribers must be explicitly clear whether the dose is based on **primaquine base** or **primaquine phosphate** (26.3 mg primaquine phosphate = 15 mg primaquine base). - **G-6-PD Deficiency**: Contraindicated in humans (and theoretically animals) with Glucose-6-Phosphate Dehydrogenase deficiency due to severe risk of hemolytic anemia. - Avoid use during pregnancy and lactation due to the risk of hemolytic anemia in fetuses/nursing neonates.
Drug interactions
- Quinacrine: May potentiate the toxicity of one another; use of primaquine within 3 months of quinacrine is not recommended.
- Bone Marrow Depressants (e.g., amphotericin B, azathioprine, chloramphenicol, antineoplastics): Concurrent use may cause an increased risk for toxicity and severe myelosuppression.
- Hemolytic Drugs (e.g., acetohydroxamic acid, sulfonylureas, quinidine, sulfonamides): Concurrent use may cause an increased risk for toxicity and hemolysis.
Frequently asked questions
What is Primaquine used for in pets?
- **Strict Dosing**: This medication has a very low safety margin when used in cats. Exact adherence to the prescribed dosage is extremely important. **Never** double-up the next dose if a dose was previously missed. - **Administration**: Give the dose with food to reduce the chance of gastrointestinal problems, particularly vomiting. - **Monitoring**: Watch your pet closely for signs of lethargy, pale or discolored gums, or breathing difficulties, and report any abnormalities to your veterinarian immediately.
Is Primaquine safe for my pet?
Dosage must be set by your veterinarian for your specific pet. Never give human medication or another pet’s prescription without veterinary guidance.
This article is for general education and is not a substitute for professional veterinary advice. If your pet is unwell, please consult a veterinarian.
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