Ketorolac
**Ketorolac** is a highly potent non-steroidal anti-inflammatory drug (NSAID) used primarily for short-term analgesia in veterinary medicine. - **Clinical Pearl**: While ketorolac provides profound pain relief (often compared to opioids in human medicine), its use in dogs and cats is highly controversial and generally discouraged due to the availability of safer, veterinary-approved NSAIDs. - It carries a very high risk of **gastrointestinal toxicity** (ulceration and perforation) and **renal toxicity**, especially with repeated dosing. - If used in dogs, most clinicians strictly limit treatment to **less than 3 days** and strongly recommend concurrent administration of gastroprotectants like **misoprostol** (with or without sucralfate).
กลไกการออกฤทธิ์: Ketorolac exerts its analgesic, anti-inflammatory, and antipyretic effects by non-selectively inhibiting **cyclooxygenase (COX-1 and COX-2)** enzymes. **Arachidonic Acid** → **COX-1/COX-2 Inhibition** → Decreased synthesis of **prostaglandins** and **thromboxanes**. By blocking prostaglandin production, it reduces inflammation and pain signaling. However, the profound inhibition of constitutive COX-1 also depletes protective prostaglandins in the gastric mucosa and kidneys, leading to its severe ulcerogenic and nephrotoxic side effect profile in small animals.
ขนาดยาตามชนิดสัตว์
- As an analgesic · 0.25 mg/kg IM q8-12h for one or two doses · IM · q8-12h · 1-2 doses
- Anterior uveitis and ulcerative keratitis · 1 drop per eye · topical · q6-24h · Frequency depends on the severity of inflammation.
- As an analgesic (Mice) · 0.7-10 mg/kg PO once daily · PO · once daily
- As an analgesic (Rats) · 3-5 mg/kg PO once to twice a day; 1 mg/kg IM once to twice a day · PO, IM · once to twice a day
- As an analgesic · 0.3-0.7 mg/kg IV , IM, SC, PO three times daily · IV, IM, SC, PO · three times daily
- As an analgesic · 0.5 mg/kg IV three times daily or 0.3 mg/kg PO twice daily · IV, PO · TID (IV) or BID (PO) · < 3 days · Repeated doses have considerable potential for causing GI or renal toxicity. Treated dogs should receive misoprostol.
- As an analgesic · 0.3-0.5 mg/kg IV , IM q8-12h for one or two doses · IV, IM · q8-12h · 1-2 doses
- Anterior uveitis and ulcerative keratitis · 1 drop per eye · topical · q6-24h · Frequency depends on the severity of inflammation.
ขนาดยาเป็นข้อมูลอ้างอิงทางคลินิกสำหรับสัตวแพทย์ผู้มีใบอนุญาต โปรดตรวจสอบกับฉลากล่าสุดและผู้ป่วยแต่ละรายเสมอ
วิธีการให้ยา
ข้อห้ามใช้
- Active GI ulcers
- History of hypersensitivity to ketorolac
- Pre-existing hematologic, renal, or hepatic disease (relative contraindication)
- Known hypersensitivity to NSAIDs
- Use with extreme caution in patients with deep or progressive corneal ulcers
อาการไม่พึงประสงค์
- Gastrointestinal ulceration and erosion
- Gastrointestinal perforation
- Renal toxicity
- Hepatic toxicity
- Platelet inhibition (increased bleeding risk)
- Local ocular irritation
- Delayed corneal epithelial healing
- Increased intraocular pressure (IOP)
- Corneal 'melting' (keratomalacia) - reported in humans, theoretical risk in animals
อันตรกิริยาระหว่างยา
- ACE INHIBITORS · Increased risk for nephrotoxicity
- ALPRAZOLAM · Hallucinations reported in some human patients taking with ketorolac
- AMINOGLYCOSIDES (gentamicin, amikacin, etc.) · Increased risk for nephrotoxicity
- ANTICOAGULANTS (heparin, LMWH, warfarin) · Increased risk for bleeding possible
- ASPIRIN · Increased likelihood of GI adverse effects (blood loss)
- BISPHOSPHONATES (alendronate, etc.) · May increase risk for GI ulceration
- CORTICOSTEROIDS · Concomitant administration with NSAIDs may significantly increase the risks for GI adverse effects
- CYCLOSPORINE · May increase risk for nephrotoxicity
- FLUCONAZOLE · May increase NSAID levels
- FLUOXETINE · Hallucinations reported in some human patients taking with ketorolac
- FUROSEMIDE · Ketorolac may reduce the saluretic and diuretic effects of furosemide
- METHOTREXATE · Serious toxicity has occurred when NSAIDs have been used concomitantly; use together with extreme caution
- MUSCLE RELAXANTS, NONDEPOLARIZING · Ketorolac may potentiate effects
การติดตาม
- Analgesic and anti-inflammatory efficacy
- Gastrointestinal signs (appetite, vomiting, diarrhea, occult blood in feces)
- Renal function parameters (BUN, creatinine, urinalysis) with repeated use
- Intraocular pressure (IOP), especially in predisposed breeds
- Corneal healing via fluorescein staining
- Signs of corneal melting or worsening ulceration
การได้รับยาเกินขนาด
Ketorolac has a narrow margin of safety in small animals. - **Cats**: Have developed renal toxicity at doses as low as 0.7 mg/kg. - **Mice**: The oral LD50 is 200 mg/kg. - **Clinical Signs**: GI effects, including severe GI ulceration and bleeding, are highly likely in overdoses in small animals. Metabolic acidosis has been reported in humans. - **Treatment**: Consider GI emptying for large, recent overdoses. Patients must be closely monitored for GI bleeding and renal impairment. Treat aggressively with GI protectants (sucralfate) and consider giving misoprostol early.
ข้อมูลอ้างอิงยาของ VetSheet มีไว้สำหรับสัตวแพทย์ผู้มีใบอนุญาตเพื่อช่วยในการตัดสินใจทางคลินิก ไม่ใช่สิ่งทดแทนการวินิจฉัยของผู้เชี่ยวชาญหรือฉลากล่าสุดของผู้ผลิต