Medicines, Sleep, Mood and Illness That Affect Memory and Focus

Why look at these first

Many cases of poor concentration or forgetfulness have a cause outside the brain's own aging: a medicine, short sleep, low mood, an illness or alcohol. Some of these can be treated or changed. This page is educational and cannot tell you which applies to you; a doctor or pharmacist can.

Medicines

Memory problems can be side effects of medicines, especially in older adults who take several. Sleep and pain medicines are the most common culprits. Examples reported by Harvard-affiliated clinicians include over-the-counter sleep aids that contain diphenhydramine (an antihistamine with anticholinergic properties, which are known to impair thinking in older people), prescription sleep drugs such as zolpidem, opioid pain medicines, tricyclic antidepressants and gabapentin. [1]

Cohort research supports caution with strong anticholinergic drugs. In 3,434 adults aged 65 and older, higher cumulative use over ten years was associated with a higher risk of dementia; the common classes were tricyclic antidepressants, first-generation antihistamines and bladder antimuscarinics. [2] This is an observational association; it does not prove the drugs caused dementia, and it does not mean any one person should stop a medicine.

What to do:

• Do not stop a medicine on your own. Track your symptoms for a week or two (when you take it, what you notice, when) and share them with your doctor. [1]


• Doctors may switch drugs, change doses or timing, or stop a drug that is no longer needed. [1] The American Academy of Neurology guideline says cognitively impairing medicines should be discontinued where possible in people with mild cognitive impairment. [3]


• Tell your doctor and pharmacist about all prescription medicines, over-the-counter products, vitamins, supplements and herbal remedies, even ones you use rarely. [4]


• See how interactions work, older adults and supplements and multiple medicines and supplement burden.

Sleep

A good night's sleep helps you learn, form memories and pay attention. [5] A meta-analysis found short-term total sleep deprivation had large effects on lapses in simple attention, [6] and another found one night of restricted sleep impaired sustained attention. [7] Sleep problems become more common with age, including insomnia, sleep apnea and restless legs syndrome. [5] Undiagnosed or untreated sleep apnea can lead to serious health problems. [5] See Insomnia, Sleep apnea and Sleep hygiene.

Mood and stress

Stress, anxiety, depression and sleeping problems are common, treatable causes of memory loss. [8] Memory problems can have other causes such as depression and anxiety, which doctors consider during an evaluation. [9] Anxiety and depression can also make ADHD symptoms worse. [10] The NIA advises getting help if you feel depressed for weeks at a time. [11] See Stress and relaxation, Anxiety disorders and Burnout. In the US, call or text 988 if you are in crisis.

Illness and recovery

• Thyroid: an underactive thyroid can cause difficulty concentrating or thinking clearly. [12]
• Vitamin B12 or folate deficiency: can cause memory, understanding and judgment problems, and delays can leave some problems irreversible. [13]
• Infections: infections such as urinary tract infections can cause sudden confusion, which is urgent. [14]
• Long COVID: symptoms can include problems with memory and concentration; NHS care teams may include cognitive rehabilitation. [15]
• Alcohol: alcohol can worsen memory loss and make some older people forgetful and confused. [16]

How strong is the evidence?

The sleep findings come from meta-analyses of experiments, so they are well supported for attention. The medicine-and-dementia finding is observational only. For stress on its own, the NHS names it as a common treatable cause of memory loss, but we did not find a source that measures how large the effect is (proper evidence not found).