How likely a condition is to be Alzheimer’s depends on age, symptoms, and timing. While Alzheimer’s is irreversible, some conditions like vitamin deficiencies or infections are treatable and even curable.

If you’re experiencing memory loss, you might wonder if you have Alzheimer’s, but it’s not always the cause. It’s important to know that several other conditions — many treatable — can mimic dementia.

It’s vital to assess risk with a healthcare professional.

Severe depression can cause memory and concentration changes that look like dementia. This is often called pseudodementia, or depressive cognitive disorder.

Depression is treatable — usually through a combination of talk therapy, medication, and lifestyle factors.

Unlike Alzheimer’s, people with “pseudodementia” often show improvement when treated with therapy or antidepressants.

Infections — especially COVID-19 or other respiratory illnesses — can lead to delirium.

The symptoms of delirium include:

These symptoms can mimic dementia. Once the underlying infection clears, the delirium goes away.

UTIs can also cause delirium, which can lead to sudden cognitive changes in older adults. UTIs in older adults often go unrecognized, as they might not display the classic symptoms of a UTI.

Unlike progressive dementia, these symptoms are often reversible with treatment — once the infection is treated, the delirium tends to go away. UTIs are usually treated with antibiotics.

Inadequate sleep can affect attention, memory, and executive function — making you feel foggy or forgetful. Your cognitive impairment might be particularly troublesome if you have a condition like sleep apnea or insomnia.

Depending on your exact condition, you may benefit from:

If you suspect you have sleep apnea or another sleep-related disorder, it’s important to make an appointment with a healthcare professional.

Not drinking enough fluids, especially in older adults, can cause confusion or dizziness. Older adults are more likely to experience dehydration than younger adults.

Rehydrating frequently reverses these effects. If you’ve been vomiting or experiencing diarrhea, it could also be a good idea to drink beverages that contain electrolytes, like sports drinks and Pedialyte.

Thyroid diseases can impact mood, memory, and thinking. This is true of hypothyroidism (an underactive thyroid) and hyperthyroidism (an overactive thyroid).

Both of these conditions can be treated. Treatment may help you think and remember more clearly.

Low B12 is relatively common. The symptoms of B12 deficiency include:

  • memory loss
  • difficulty concentrating
  • fatigue
  • mood changes

A vitamin B12 deficiency can be diagnosed using a blood test. The symptoms often get better with oral supplements or injections. You can also try to eat more vitamin B12-rich foods.

If blood sugar drops too low, it can cause confusion or memory concerns.

Consistent diabetes care can help prevent or reverse these symptoms. This includes taking your medication as instructed and eating a doctor-approved diet.

Some medications can impair thinking, including:

If you’re experiencing cognitive changes, one or more of your medications may be at fault. Do not change or discontinue use without first consulting your prescribing physician.

Excess cerebrospinal fluid can build up in the skull, a condition called hydrocephalus or “water on the brain.” This fluid can press on brain structures, leading to symptoms like memory changes and difficulty walking.

Left untreated, hydrocephalus can be dangerous. This condition can sometimes be treated surgically.

After a head injury, slow bleeding in the brain can cause confusion, personality changes, or difficulty with memory.

While it’s relatively rare, this condition is serious. A subdural hematoma can be diagnosed using imaging tests, like a CT or MRI scan. It’s treated with surgery.

If memory, confusion, or mood changes appear suddenly — or progress rapidly — it’s critical to seek medical help.

A full evaluation may involve:

  • Physical and mental health history
  • Physical exam and cognitive testing
  • Blood tests (for B12, thyroid, infection indicators)
  • Imaging scans when needed (e.g., to spot bleeding or hydrocephalus)

These steps can help healthcare professionals diagnose your condition and guide you to the right treatment.

Memory loss or confusion doesn’t always mean Alzheimer’s. Many common conditions — like depression, infections, sleep disorders, or vitamin deficiencies — can cause similar symptoms but get better with treatment.

Finding and treating these conditions early can make a huge difference in quality of life. If you suspect you have dementia or any of the above conditions, it’s a good idea to book an appointment with a healthcare professional.