See also October 2006 Drug Update "How to Avoid Drug Interactions in the Elderly."

Drug–drug interactions can have potentially life-threatening consequences in older adults, who often take several drugs at once for multiple diseases. Elderly patients are more susceptible to drug interactions than younger patients because of the physiologic changes associated with aging and the sheer number of drugs older patients are taking.

Drugs to avoid in patients ≥65 years:
Analgesic/anti-inflammatory
• Indomethacin
• Ketorolac
• Long-term use of full-dose, longer half-life, non–COX-selective NSAIDs: naproxen, oxaprozin, and piroxicam
• Meperidine
• Pentazocine
• Propoxyphene and propoxyphene combination products

Cardiovascular
• Amiodarone
• Clonidine
• Digoxin
• Disopyramide
• Doxazosin
• Guanadrel
• Methyldopa and methyldopa-hydrochlorothiazide
• Reserpine, >0.25 mg
• Short-acting dipyridamole
• Short-acting nifedipine
• Ticlopidine

Diabetic agents
• Chlorpropamide

Gastrointestinal
• Cimetidine
• Gastrointestinal antispasmodic drugs: dicyclomine, hyoscyamine, propantheline, belladonna alkaloids, and clindinium-chlordiazepoxide
• Long–term use of stimulant laxatives: bisacodyl, cascara sagrada, Neoloid, except when used with opiate analgesic
• Mineral oil
• Trimethobenzamide

Muscle relaxants
• Ditropan XL
• Muscle relaxants, antispasmodics: methocarbamol, carisoprodol, chlorzoxazone, metaxalone, cyclobenzaprine, oxybutynin
• Orphenadrine

Psychotropics
• Amitriptyline, chlordiazepoxide-amitriptyline, perphenazine-amitriptyline
• Amphetamines, anorexic agents
• Barbiturates (except phenobarbital), except for seizures control
• Benzodiazepines (short-acting): doses >3 mg lorazepam; >60 mg oxazepam; >2 mg alprazolam; >15 mg temazepam; >0.25 mg triazolam
• Benzodiazepines (long-acting): chlordiazepoxide, chlordiazepoxide-amitriptyline,
• clidinium-chlordiazepoxide, diazepam, quazepam, halazepam, chlorazepate
• Doxepin
• Ergot mesyloids, cyclandelate
• Fluoxetine, daily dose
• Flurazepam
• Guanethidine
• Meprobamate
• Mesoridazine
• Thioridazine

Respiratory
• Anticholinergics, antihistamines: chlorpheniramine, diphenhydramine, hydroxyzine,
• cyproheptadine, promethazine, tripelennamine, dexchlorpheniramine
• Diphenhydramine

Source: Arch Intern Med. 2003;163:2716-2724.

The latest update of the Beers criteria for potentially inappropriate drugs in the elderly is available at www.archinte.ama-assn.org/cgi/content/full/163/22/2716