majiayu000 Veterinary Contraindication Checker
Overview
Systematic contraindication checking for veterinary drug therapy. Goes beyond drug-drug interactions (see drug-interaction-checker) to evaluate patient-specific factors that may make a drug unsafe: species, breed genetics, organ dysfunction, pregnancy, age extremes, and concurrent disease states.
When to Use
- Before recommending any drug therapy in a veterinary patient
- When a patient has known organ dysfunction (renal, hepatic, cardiac)
- When a patient is pregnant, lactating, or neonatal
- When breed-specific drug sensitivities may apply
- Keywords: contraindication, safe to use, can I give, renal dose, hepatic dose, pregnant, breeding, puppy, kitten, geriatric
Contraindication Categories
Species Contraindications
See lethal-variance-detection skill. Some drugs are absolutely contraindicated in certain species regardless of patient status.
Breed/Genetic Contraindications
- MDR1 mutation (ABCB1): Ivermectin (high dose), loperamide, acepromazine (use lower dose), vincristine, doxorubicin -- affected breeds: Collie, Australian Shepherd, Shetland Sheepdog, Old English Sheepdog, and crosses
- Greyhounds/Sighthounds: Prolonged thiopental recovery, different propofol pharmacokinetics, lower normal reference ranges for some lab values
- Brachycephalic breeds: Higher anesthesia risk, avoid heavy sedation protocols, caution with opioid-induced respiratory depression
Organ Function Contraindications
- Renal insufficiency: Adjust or avoid nephrotoxic drugs (aminoglycosides, cisplatin, NSAIDs). Reduce doses of renally excreted drugs.
- Hepatic insufficiency: Avoid hepatotoxic drugs (ketoconazole, azathioprine at standard doses). Reduce doses of hepatically metabolized drugs.
- Cardiac disease: Avoid negative inotropes in heart failure patients. Caution with fluid-loading drugs.
- GI disease: Consider route of administration; oral drugs may have unpredictable absorption.
Life Stage Contraindications
- Neonatal/Pediatric: Many drugs lack pediatric dosing data. Immature hepatic and renal function affects clearance. Fluoroquinolones avoid in growing animals (cartilage damage).
- Geriatric: Reduced organ reserve. Start low, go slow. More susceptible to adverse effects.
- Pregnant/Lactating: Many drugs are teratogenic or excreted in milk. Griseofulvin is teratogenic in cats. Methotrexate, retinoids are contraindicated.
Disease State Contraindications
- Seizure history: Avoid drugs that lower seizure threshold (fluoroquinolones, tramadol in some patients)
- Bleeding disorders: Avoid NSAIDs and drugs affecting platelet function
- GDV/GI obstruction: Oral medications may not be absorbed; avoid prokinetics if mechanical obstruction
Workflow
- List all patient parameters: species, breed, age, weight, reproductive status, known organ dysfunction, concurrent diseases, current medications.
- For each proposed drug, check against all applicable contraindication categories.
- If a contraindication is found, classify severity:
- Absolute: Do not use under any circumstances
- Relative: Use only if benefit clearly outweighs risk, with monitoring
- Dose adjustment: Drug may be used at modified dose or frequency
- Suggest alternatives when a drug is contraindicated.
Limitations
- Contraindication data is most complete for dogs and cats. Exotic species data is limited.
- Clinical judgment may override relative contraindications when no suitable alternative exists.
- New contraindications are discovered through post-market surveillance and case reports.