Selected Analgesics for Use in Cats
Drug | Class | Pain category | Intermittent dosage regimen | Epidural dosage | CRIa dosage regimen | Comments |
|---|---|---|---|---|---|---|
Alfentanil | Opioid | Acute | NA—very short acting | NA—very short acting | 5–10 mcg/kg IV followed by 0.8–1 mcg/kg/minute IV CRI | DEA Schedule II. Short-acting opioid given by CRI to achieve effect. |
Bupivacaine | Local anesthetic | Acute | Injectable solution: 1.1 mg/kg locally (not IV) | Preservative-free injectable 0.5% solution: 1.5–2.5 mg/kg | Not for IV use | Not for IV use. Systemic administration has resulted in severe cardiac and CNS toxicity including death. Products combined with epinephrine will prolong the duration of local effect and reduce the likelihood of systemic toxicity. |
Buprenorphine | Opioid partial antagonist/agonist | Acute | Injectable 0.03% solution: 0.01–0.03 mg/kg IV, IM, or transmucosal q 4–8 h; Long-acting injection: 0.24 mg/kg SC q 24 h for up to 3 days. Transmucosal 2% solution: 2.7–6.7 mg/kg q 96 h | Injectable 0.03% solution: 0.005–0.01 mg/kg, followed by 0.002–0.004 mg/kg/h IV CRI | DEA Schedule III. Do not confuse dosing for long-acting concentrated 1.8 mg/ml injection (approved for cats) with 0.3 mg/ml injection (approved for humans). | |
Butorphanol | Opioid partial antagonist/agonist | Acute | 0.2–0.4 mg/kg IV, IM, or SC q 1–2 h | 0.2–0.4 mg/kg IV followed by 0.1–0.24 mg/kg/h IV CRI | DEA Schedule IV. | |
Carprofen | NSAID | Acute/chronic | 4 mg/kg SC, IV for one dose only | Not for epidural use | Not for CRI | Do not administer more than one dose to cats. |
Dexmedetomidine | Alpha-2 adrenergic receptor agonist | Acute | 5–40 mcg/kg IM, SC, or IV but likely to cause emesis at these dosages | 0.5 mcg/kg IV followed by 0.5 mcg/kg/h IV CRI | Dexmedetomidine causes emesis in cats with dosages of 6–18 mcg/kg IM or 3.5 mcg/kg IV. Transmucosal dexmedetomidine is not typically used for analgesia in cats. | |
Fentanyl | Opioid | Acute | Transdermal patch: 0.001–0.005 mg/kg/h rounded to the nearest 12.5 mcg or 25 mcg | Preservative free: 0.004 mg/kg | 0.01 mg/kg IV followed by 0.01 mg/kg/h IV CRI | DEA Schedule II. Note delayed onset of analgesia (6–24 h) limits utility as an initial monotherapy for acute pain. |
Gabapentin | GABAb receptor agonist | Chronic | 3–10 mg/kg PO q 8–12 h | Not for epidural use | Not for IV use | Gabapentin is a reportable controlled substance in some states in the US. |
Hydromorphone | Opioid | Acute | 0.05–0.1 mg/kg IV, IM, or SC q 2–6 h; likely to cause emesis at this dosage | 0.03–0.05 mg/kg | 0.025 mg/kg IV followed by 0.01–0.05 mg/kg/h IV CRI | DEA Schedule II. Causes emesis in cats at dosages of 0.1 mg/kg SC. |
Ketamine | NMDAc receptor antagonist | Acute | 3–5 mg/kg IV as a perioperative analgesic adjunctive therapy | Not recommended | 0.5–1 mg/kg IV followed by 0.1–0.6 mg/kg/h IV CRI | DEA Schedule III. Ketamine may be neurotoxic when administered by the epidural or intrathecal route. |
Lidocaine | Local anesthetic | Acute | 2–4 mg/kg local infiltration | Preservative free: 4.4 mg/kg | Not recommended | Cats are sensitive to the CNS and cardiovascular effects of lidocaine. |
Maropitant | NK-1d receptor antagonist | Acute | 1 mg/kg SC, IV | Not for epidural use | 1 mg/kg IV over 1–2 minutes followed by 0.1 mg/kg/h IV CRI | Rapid injection of maropitant by the intravenous route may cause severe hypotension. Refrigerating the injection may reduce the pain associated with SC injection. |
Meloxicam | NSAID | Acute/chronic | 0.3 mg/kg SC once; 0.1 mg/kg PO once followed by 0.05 mg/kg PO q 24 h tapered to the lowest effective dose | Not for epidural use | Not for IV use | Black box warning on US products stating that repeated use of meloxicam in cats has been associated with acute renal failure and death. |
Methadone | Opioid | Acute | 0.05–0.5 mg/kg IV, SC, or IM q 4–6 h | 0.3 mg/kg | 0.1–0.2 mg/kg IV followed by 0.12 mg/kg/h IV CRI | DEA Schedule II. |
Morphine | Opioid | Acute | 0.1–0.25 mg/kg IV, IM, or SC q 2–4 h | Preservative free: 0.1 mg/kg | 0.1–0.25 mg/kg IV followed by 0.05–0.1 mg/kg/h IV CRI | DEA Schedule II. Rapid IV administration causes CNS excitation. May cause hyperthermia in cats. |
Prednisolone | Corticosteroid | Chronic | 1–2 mg/kg PO q 24 h | Not for epidural use | Not for IV use | Do not use concurrently with NSAIDs. |
Pregabalin | GABA receptor agonist | Chronic | 1 mg/kg PO q 8–12 h | Not for epidural use | Not for IV use | DEA Schedule IV. |
Remifentanil | Opioid | Acute | NA due to extremely short duration of action | NA due to extremely short duration of action | 2.5 mcg/kg IV bolus followed by 0.2–0.4 mcg/kg/minute IV CRI | DEA Schedule II. |
Robenacoxib | NSAID | Acute/chronic | 2 mg/kg SC for up to 3 days; 1 mg/kg PO q 24 h | Not for epidural use | Not for IV use | |
Ropivacaine | Local anesthetic | Acute | 1.5–2 mg/kg as a local infiltration | Not for IV use | Not for IV use. Systemic administration has resulted in severe cardiac and CNS toxicity including death. | |
Sufentanil | Opioid | Acute | NA | 0.5–1 mcg/kg | 0.5–1 mcg/kg slow IV followed by 0.5–1 mcg/kg/h IV CRI | DEA Schedule II. |
Tramadol | Synthetic opioid | Acute/chronic | 1–2 mg/kg PO q 12 h | Not for epidural use | Not for IV use | DEA Schedule IV. |
a CRI=constant-rate infusion. b GABA=gamma-aminobutyric acid. c NMDA=N-methyl-D-aspartate. d NK-1=neurokinin-1. | ||||||