title: Geriatric pharmacology.
abstract: When faced with the geriatric dog or cat, the practitioner should consider the following: 1. Avoid using any drugs at all unless there are definite therapeutic indications. If the patient has some degree of renal insufficiency, try to select drugs that are hepatically metabolized and excreted in bile rather than eliminated by the kidneys (eg, doxycycline, tolfenamic acid). If hepatic insufficiency is present, select drugs that do not undergo metabolism before renal excretion (eg, penicillins, cephalosporins). 2. If therapeutic drug monitoring is available, tailor the drug dosage regimen to that specific patient (eg, phenobarbital, digoxin, amino-glycosides). 3. If therapeutic drug monitoring is unavailable, determine if there are clinically proven adjusted dosage regimens for specific drugs. The package insert on human pharmaceutics often gives guidelines for adjusting dosages in geriatric patients. 4. If the drug has not been sufficiently studied to have dosage adjustment recommendations, determine if there is sufficient information about its kinetics to estimate the proper drug dose in a geriatric patient. Some general guidelines for commonly used drugs in geriatric veterinary patients are provided in Table 1. In general, if the Vd changes in your patient, change the dose. If the elimination half-life changes, change the dosing interval. 5. Carefully monitor treated patients for signs of efficacy and toxicity.
authors.affiliation: Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, 52 Campus Drive, Saskatoon, Saskatchewan S7N 5B4, Canada. trishaw.dowling@usask.ca
authors.forename: Patricia M
authors.initials: PM
authors.lastname: Dowling
mesh_terms: D000375:Aging / Q000473:pathology / Q000502:physiology*; D000820:Animal Diseases / Q000188:drug therapy*; D000818:Animals; D001682:Biological Availability; D002318:Cardiovascular Diseases / Q000188:drug therapy / Q000662:veterinary; D004305:Dose-Response Relationship, Drug; D004334:Drug Administration Schedule / Q000662:veterinary; D007408:Intestinal Absorption; D007674:Kidney Diseases / Q000188:drug therapy / Q000662:veterinary; D008107:Liver Diseases / Q000188:drug therapy / Q000662:veterinary; D016896:Treatment Outcome; D019155:Veterinary Drugs / Q000493:pharmacokinetics* / Q000494:pharmacology*
chemical_list: D019155:Veterinary Drugs