Older Adults and Multiple Medicines

Cannabis use is rising among older adults, but the research on this age group is thin. This page explains what health agencies and reviews say about falls, thinking, sleep and medicine interactions. It is education only. Nobody should start, stop or change a prescription because of this page; a prescriber or pharmacist who knows your full medicine list is the right person to ask.

How evidence is labeled here. Evidence of harm (association) means studies link use with a worse outcome. Insufficient evidence means too little good research to say. No good evidence of benefit means studies looked and did not find a clear benefit. Mixed means findings disagree.

Who is using cannabis, and why

NIDA reports that adults aged 50 and older have had the largest increase in cannabis use of any age group, with the greatest increase among those 65 and older. [1] It says older adults mainly use cannabis to self-treat chronic conditions such as pain, sleep problems, anxiety and depression. [1] It also says cannabis may affect the brain differently in older adults than in younger people. [1]

The research gap

A 2021 review noted that knowledge about cannabis, brain health, injury risk and drug interactions in older adults remains limited, because most evidence comes from adolescent and young adult groups plus a small number of small observational studies in older people. [2] An older pharmacy review reached a similar view: reputable literature on the effect of marijuana in older adults is scarce. [3] Label: insufficient evidence for many questions specific to older adults.

Falls, dizziness and injury

NCCIH says cannabis use is associated with an increased risk of injury among older adults. [4] It adds that marijuana may cause orthostatic hypotension, a head rush or dizziness on standing up, possibly raising the danger of fainting and falls. [4] The pharmacy review points out that older adults often have several health conditions and take several medicines, and that cannabis adds to sedating effects on the central nervous system. [3] For the FDA, combining CBD with alcohol or other drugs that slow brain activity raises the risk of sedation and drowsiness, which can lead to injuries. [5] Label: evidence of harm (association) for injury. For fall prevention in general, see falls and balance.

Sleep claims

Sleep is one of the most common reasons older adults give for using cannabis. A 2026 review found that evidence for effectiveness, tolerability and safety in older adults is limited, that most experimental studies were done in younger adults, and that people's sense of better sleep is often not supported by objective sleep measurements. [6] It calls rigorous studies enrolling older adults "virtually nonexistent" and says evidence for CBD and CBN in sleep remains sparse. [6] Label: insufficient evidence. See also cannabis for sleep: evidence review.

Dementia

A Cochrane review included four small trials (126 participants, mostly with Alzheimer's disease) of THC-type medicines. It found low-certainty evidence of little or no clinically important effect on behavioral and psychological symptoms of dementia, and the authors said they could not be certain whether cannabinoids have beneficial or harmful effects. [7] Sedation was more frequent with nabilone (a prescription cannabinoid medicine) than with placebo in one crossover study. [7] Label: insufficient evidence; no good evidence of clear benefit so far. More at mild cognitive impairment and dementia.

Medicines and interactions

NIDA says cannabis may interact with medicines older adults may take, such as warfarin, opioids and benzodiazepines. [1] THC and CBD are broken down by the same liver enzymes (CYP3A4, CYP2C9 and CYP2C19) that handle most prescription medicines. [8] A 2024 systematic review found 31 real-world reports of cannabinoids changing blood levels or causing side effects of medicines with a narrow safety margin. Warfarin, valproate, tacrolimus and sirolimus were the most widely reported, and the side effects included bleeding risk, altered mental status and gastrointestinal distress. [8]

For warfarin specifically, a separate review found only seven case reports. It rated the data very low quality and said they support a potential interaction with both THC and CBD, with raised INR (a blood clotting measure) in six of the seven cases. [9] Label: insufficient evidence (very low-quality reports of possible harm). The practical point is to tell the prescriber and pharmacist about any cannabis or CBD product. Details are in CBD-medication interactions and how supplement interactions work.

The prescription CBD label

The label for the approved CBD medicine Epidiolex says its trials did not include enough people over 55 to know whether they respond differently. It notes that older people more often have reduced liver, kidney or heart function and take other medicines. [10] That is a prescription product for specific seizure disorders and is separate from consumer products. See approved cannabinoid medicines and liver considerations.

Questions to bring to a prescriber or pharmacist

• Which of my medicines are processed by the liver or have a narrow safety margin?
• Could this product add to drowsiness, dizziness or fall risk?
• What symptoms should make me call you?

For general guidance see older adults and natural remedies and medicines and supplement burden.