Role of feline specific features in drug safety

Cats exhibit unique physiological, anatomical, and metabolic traits that significantly impact the pharmacokinetics of drugs, including their absorption, distribution, metabolism, and excretion. These differences, when compared to other companion animals, particularly dogs, result in a distinct sensitivity to many commonly used medications. This review aims to evaluate the pharmacological risks associated with major drug classes used in feline medicine, including antibiotics, antiparasitic agents, non-steroidal anti-inflammatory drugs, and opioids, while highlighting the role of feline-specific physiological and metabolic characteristics in drug safety. A key concern in feline pharmacology is the presence of species-specific enzyme deficiencies, most notably glucuronyl transferase and thiopurine methyltransferase. These deficiencies impair the liver's ability to conjugate and detoxify drugs, leading to a heightened risk of adverse effects and systemic toxicity. Several drug classes commonly used in feline medicine are associated with clinically relevant adverse effects; aminoglycosides may cause nephrotoxicity, whereas tetracyclines have been linked to dental discoloration and oesophageal injury. Fluoroquinolones are known to induce retinal degeneration and potential blindness in cats, and acetaminophen is highly hepatotoxic and often fatal, even at low doses. The primary objective of this review is to provide veterinarians with a comprehensive understanding of the pharmacological risks associated with drug use in cats, thereby facilitating more informed and evidence-based prescribing decisions. In light of the species-specific physiological and metabolic characteristics of cats, individualised dosing protocols and appropriate therapeutic alternatives should be considered to enhance drug safety and minimise the risk of severe or potentially life-threatening adverse drug reactions.