Abstract / Summary
Polypharmacy, multimorbidity, and exposure to potentially inappropriate or otherwise higher-risk medications contribute to adverse drug events, falls, cognitive impairment, and treatment burden in older adults. Cannabis and cannabinoid use is also increasing, often for symptoms already treated with conventional medicines. We conducted a targeted narrative review using iterative PubMed/MEDLINE searches from database inception through September 2026. Searches addressed older adults, polypharmacy and medication optimization, medication reduction and substitution, chronic and neuropathic pain, sleep, anxiety and mood, spasticity and multiple sclerosis, palliative and supportive care, adverse effects, drug interactions, and older-adult pharmacology. Evidence is most developed for selected chronic pain outcomes and multiple-sclerosis-related spasticity, whereas evidence for sleep, anxiety, mood, and many supportive-care outcomes remains less certain and is particularly sparse in older adults. Observational studies report self-reported substitution and reductions in opioid and other medication use after cannabis initiation, but these findings do not establish clinician-directed deprescribing or improvement in the overall medication regimen. Cannabinoid-related dizziness, sedation, cognitive and cardiovascular effects, and drug interactions may offset potential medication-sparing benefits. Cannabinoid initiation alone is not medication optimization. Addition, substitution, observed medication reduction, clinician-directed deprescribing, and medication optimization describe different clinical actions or outcomes and should not be treated interchangeably. In selected older adults, cannabinoid therapy may create an opportunity to reassess higher-risk or duplicative therapy, but optimization requires evidence that the resulting regimen preserves or improves symptom control, function, safety, treatment burden, and patient goals without introducing disproportionate cannabinoid-related harm.