Introduction

• Polypharmacy (using multiple drugs at the same time in the same patient) is sometimes unavoidable in patients with multiple acute or chronic medical problems, particularly in the perioperative period. However, the risk of drug interactions (and adverse effects) multiplies as the number of administered drugs increases.
• Interactions can occur during:
  • IV drug administration.
  • Oral absorption, at the target site (either antagonistic or synergistic effects).
  • Hepatic or renal elimination.
• Any of these interactions may lead to loss of efficacy or increased risk of toxicity.
• Although virtually all of knowledge of drug interactions is from data in humans, many of these interactions are also likely to occur in veterinary patients.

The top potential offenders for drug interactions in the perioperative period

Further Reading

Publications

Refereed papers

•  Recent references from PubMed and VetMedResource.
• Morgan T & Anderson A (2003) The effect of nonsteroidal anti-inflammatory drugs on blood pressure in patients treated with different antihypertensive drugs. J Clin Hypertens (Greenwich) 5 (1), 53-57 PubMed.
• Rengelshausen J, Göggelmann C, Burhenne J et al (2003) Contribution of increased oral bioavailability and reduced nonglomerular renal clearance of digoxin to the digoxin-clarithromycin interaction. Br J Clin Pharmacol 56 (1), 32-38 PubMed.
• Abebe W (2002) Herbal medication: potential for adverse interactions with analgesic drugs. J Clin Pharm Ther 27 (6), 391-401 PubMed.
• Lotsch J, Skarke C, Tegeder I et al (2002) Drug interactions with patient-controlled analgesia. Clin Pharmacokinet 41 (1), 31-57 PubMed.
• Mealey K L (2002) Clinically significant drug interactions. Compendium of Continuing Education for Practicing Veterinarians 24 (1), 10-22 VetMedResource.
• Mercadante S, Villari P, Ferrera P (2002) Itraconazole-fentanyl interaction in a cancer patient. J Pain Symptom Manag 24 (3), 284-286 PubMed.
• Slagle M A (2001) Medication update. Southern Med J 94 (6), 574-578 PubMed.
• Dresser G K, Spence J D & Bailey D G (2000) Pharmacokinetic-pharmacodynamic consequences and clinical relevance of cytochrome P450 3A4 inhibition. Clin Pharmacokinet 38 (1), 41-57 PubMed.
• Foster S F, Church D B & Watson A D (2000) Effect of phenobarbitone on the low-dose dexamethasone suppression test and the urinary corticoid: creatinine ratio in dogs. Aust Vet J 78 (1), 19-23 PubMed.
• Lomaestro B M & Piatek M A (1998) Update on drug interactions with azole antifungal agents. Ann Pharmacother 32 (9), 915-928 PubMed.
• Müller F O, Middle M V, Schall R et al (1997) An evaluation of the interaction of meloxicam with frusemide in patients with compensated chronic cardiac failure. Br J Clin Pharmacol 44 (4), 393-398 PubMed.
• Balant-Gorgia A E, Ries C & Balant L P (1996) Metabolic interaction between fluoxetine and clomipramine: a case report. Pharmacopsychiatry 29 (1), 38-41 PubMed.
• Mizuki Y, Fujiwara I & Yamaguchi T (1996) Pharmacokinetic interactions related to the chemical structures of fluoroquinolones. J Antimicrob Chemother 37 (Suppl A), 41-55 PubMed.
• Intorre L, Mengozzi G, Maccheroni M et al (1995) Enrofloxacin-theophylline interaction: influence of enrofloxacin on theophylline steady-state pharmacokinetics in the beagle dog. J Vet Pharmacol Ther 18 (5), 352-356 PubMed.
• Trepanier L A (1995) Use of bromide as an anticonvulsant for dogs with epilepsy. J Am Vet Med Assoc 207 (2), 163-166 PubMed.
• Munn J, Tooley M, Bolsin S et al (1993) Effect of metoclopramide on renal vascular resistance index and renal function in patients receiving a low-dose infusion of dopamine. Br J Anaesth 71 (3), 379-382 PubMed.
• Andersson T (1991) Omeprazole drug interaction studies. Clin Pharmacokinet 21 (3), 195-212 PubMed.
• Brooks P M & Day R O (1991) Nonsteroidal anti-inflammatory drugs - differences and similarities. New Eng J Med 324 (24), 1716-1725 PubMed.
• Cull D L, Lally K P & Murphy K D (1991) Compatibility of packed erythrocytes and Ringer's lactate solution. Surg Gynecol Obstet 173 (1), 9-12 PubMed.
• Reynolds J C (1990) The clinical importance of drug interactions with antiulcer therapy. J Clin Gastroenterol 12 (Suppl 2), S54-63 PubMed.
• Atkins C E, Snyder P S & Keene B W (1988) Effect of aspirin, furosemide, and commercial low-salt diet on digoxin pharmacokinetic properties in clinically normal cats. J Am Vet Med Assoc 193 (10), 1264-1268 PubMed.
• Somogyi A & Muirhead M (1987) Pharmacokinetic interactions of cimetidine 1987. Clin Pharmacokinet 12 (5), 321-366 PubMed.
• Webster J (1985) Interactions of NSAIDs with diuretics and beta-blockers mechanisms and clinical implications. Drugs 30 (1), 32-41 PubMed.
• Sedman A J (1984) Cimetidine-drug interactions. Am J Med 76 (1), 109-114 PubMed.
• Reilly P E & Isaacs J P (1983) Adverse drug interactions of importance in veterinary practice. Vet Rec 112 (2), 29-33 PubMed.
• Dickson D N & Gregory M A (1980) Compatibility of blood with solutions containing calcium. S Afr Med J 57 (19), 785-787 PubMed.
• Pedersoli W M, Ganjam V K & Nachreiner R F (1980) Serum digoxin concentrations in dogs before, during, and after concomitant treatment with phenobarbital. Am J Vet Res 41 (10), 1639-1642 PubMed.
• Adelman R D, Spangler W L, Beasom F et al (1979) Furosemide enhancement of experimental gentamicin nephrotoxicity: comparison of functional and morphological changes with activities of urinary enzymes. J Infect Dis 140 (3), 342-52 PubMed.