Alzheimer’s Disease Symptoms

Medically Reviewed by Shruthi N, MD on July 02, 2024
Written by Rachel Reiff Ellis
7 min read

Alzheimer's is a brain disease that causes a decline in your memory, thinking, reasoning, and organization skills, eventually impairing your ability to do daily basic tasks.

It’s one form of dementia. Dementia is a broad term to describe a decline in mental function, and Alzheimer’s is a specific disease underneath that umbrella. Different types of dementia can have similar symptoms, and it’s also possible to have more than one type at a time, so it can be hard to know if what you have is Alzheimer’s. 

Alzheimer’s is the most common form of dementia, accounting for more than two-thirds of cases in people over 65. The symptoms of Alzheimer's disease often come on slowly, over several years. Memory loss that gets worse over time is a hallmark of the disease.

There are different Alzheimer’s symptom stages. Early Alzheimer’s symptoms might start when someone has trouble recalling things that just happened or putting thoughts into words. But over time, the problems get worse. People in the later stages of the disease usually can’t live alone or care for themselves.

There are three main phases of Alzheimer's: mild, moderate, and severe. Each stage has its own set of symptoms. 

The first stage usually lasts from 2 to 4 years. The symptoms include:

  • Having less energy and drive to do things
  • Less interest in work and social activities, and spending more time just sitting, watching TV, or sleeping
  • Loss of recent memories, like forgetting conversations and events that just happened
  • Language problems, like trouble putting thoughts into words or understanding others
  • Mild coordination problems, such as trouble writing or using familiar objects.
  • A hard time with everyday tasks, such as following a recipe or balancing a checkbook
  • Mood swings that involve depression or a lack of interest
  • Trouble with driving, like getting lost on familiar routes

Diseases that mimic Alzheimer's

When a person has one or a few of these issues, it doesn’t necessarily mean they have Alzheimer's. There are other medical conditions that can cause the same problems, such as:

  • Conditions that affect metabolism, such as a thyroid problem. These conditions are typically treatable, and the cognitive symptoms usually get better once the disease is under control. 
  • Drug abuse. If your loved one is misusing drugs or alcohol, especially if this is a long-held habit, they may have cognitive problems that look like Alzheimer’s disease. You may notice certain physical signs with substance abuse, like more frequent injuries and falls, high blood pressure, or problems sleeping.
  • Taking medications that don’t work well together. Review medications with a doctor – including any supplements – to be sure the mixture isn’t causing problems with mental skills. 
  • Parkinson's disease. While Parkinson’s disease is also a disorder that can affect thinking in later stages, the primary symptoms affect movement. You should notice more of these signs early on, such as tremor.
  • Stress. Stress can crowd out your normal ability to think clearly. This should go away if you are able to reduce your stress, while cognitive problems with Alzheimer’s get steadily worse.
  • Depression. Poor thinking ability and memory problems are very common symptoms of depression. Treatment for depression with counseling and perhaps medication typically reduces this issue.

A doctor can check on these symptoms and do tests to know if a person has Alzheimer’s or something else.

This is when memory loss gets worse and starts to cause problems in daily life. This stage of Alzheimer’s symptoms can last from 2 to 10 years.

Someone with moderate Alzheimer's may start to forget details about their life, like where they went to high school or when they got married. They may not recognize or remember family members and friends. They might also forget where they leave things and can’t retrace their steps to find them.

Other Alzheimer’s symptoms at this stage can include:

  • Rambling speech
  • Trouble coming up with the right words and using the wrong ones
  • A hard time planning or solving problems
  • Confusion about time or place. They may get lost in places they have been before. Once they are there, they may not know how or why they got to that place.
  • Not dressing for the weather
  • Getting angry or upset easily, sometimes lashing out at family or caregivers
  • Trouble sleeping
  • Wandering
  • Delusions, such as thinking a caregiver is trying to hurt them

Some people with moderate Alzheimer’s symptoms also become more aware that they’re losing control of their lives, which can make them even more frustrated or depressed.

The third stage, also known as late Alzheimer's, is the most severe. It typically lasts 1 to 3 years.

People in this phase might have some or all of these Alzheimer’s symptoms:

  • Major confusion about what’s in the past and what’s happening now
  • Can’t express themselves, remember, or process information
  • Problems with swallowing and control of their bladder and bowels
  • Weight loss, seizures, skin infections, and other illnesses
  • Extreme mood swings
  • Seeing, hearing, or feeling things that aren’t really there, called hallucinations
  • Can’t move easily on their own

There are several physical symptoms someone with Alzheimer’s disease may have, such as:

  • Balance problems
  • Tripping and falling
  • Dragging feet or shuffling when walking
  • Weak or stiff muscles
  • Twitches or seizures
  • Trouble sitting or standing
  • Apraxia, the general term for a loss of voluntary motor function

The last stages of Alzheimer’s can affect the brain and result in physical symptoms such as:

  • Inhaling food or liquid into the lungs
  • Flu, pneumonia, and other infections
  • Falls
  • Fractures
  • Bedsores
  • Poor nutrition or dehydration
  • Constipation or diarrhea
  • Dental problems such as mouth sores or tooth decay

Alzheimer’s symptoms typically show up in later life, after age 65. When Alzheimer’s disease happens in someone younger than age 65, it's known as early-onset (or younger-onset) Alzheimer’s disease. 

There aren’t many differences between early-onset Alzheimer’s disease symptoms and Alzheimer’s disease symptoms. You may notice you:

  • Forget newly learned information or important dates
  • Ask for the same information repeatedly
  • Have trouble solving basic problems, such as following a recipe
  • Lose track of the date or time of year
  • Have bouts of not remembering where you are and how you got there
  • Have issues with depth perception or other vision problems
  • Have a hard time joining conversations or finding the right word for something
  • Misplace things and aren’t able to retrace your steps to find them
  • Withdraw from work and social situations
  • Have changes in your mood and personality

Just about everyone has minor memory glitches as they get older. If someone forgets a name or why they walked into the kitchen, that doesn't mean they have Alzheimer's.

The main problem that defines the disease is trouble planning and handling day-to-day tasks, like paying bills, managing a checkbook, or using familiar appliances around the house.

A typical brain shrinks some with age, but the neurons (nerve cells) in the brain aren’t affected in large numbers. When you have Alzheimer’s disease, a number of neurons are damaged, stop working, and eventually die. 

These neurons tend to be in the parts of the brain involved with memory. That’s why the first and most prominent symptoms are related to remembering, thinking, and reasoning.

In the later stages of the disease, the damage to the brain is more widespread, and it affects communication and the ability to do daily tasks. 

If you think you notice the signs of Alzheimer’s in yourself or a loved one, the best thing to do is to talk to a doctor. They can let you know what the symptoms mean and what your options are for treating them. 

Although there’s no single test that can give you a positive result for Alzheimer’s disease, new advances can help with early detection and treatment. 

One is as simple as a blood test to determine the presence or absence of proteins that may mean there are plaques linked to Alzheimer’s in the brain. Your doctor may also use:

  • Neurological exams
  • Cognitive and functional assessments 
  • Brain imaging (MRI, CT, PET) 
  • Cerebrospinal fluid tests

The combination of all this diagnostic information can help form a bigger picture for your doctor. 

Alzheimer's disease is a brain disorder that is the most common type of dementia. The hallmark symptom is memory loss, but other symptoms are problems with sound thinking, judgment impairment, confusion, and behavior changes. Alzheimer’s disease has three stages: mild, moderate, and severe. Symptoms come on slowly and get worse over time

What are the three types of behavioral triggers in Alzheimer's?

As Alzheimer’s symptoms progress, the disease can trigger behavior changes. These changes include agitation (physical or verbal aggression, general emotional distress,

restlessness, pacing, shredding paper or tissues, and/or yelling); delusions (firmly held beliefs in things that are not real); and hallucinations (seeing, hearing, or feeling things that are not there).

When do Alzheimer's symptoms start?

Most people with Alzheimer’s have symptoms after age 65. But a few have early-onset Alzheimer’s, which triggers symptoms in your 30s or 40s. Symptoms can be hard to spot in the early stages and are often mistaken for normal signs of aging. 

Do patients with Alzheimer's sleep a lot?

Sleeping a lot is common with Alzheimer’s, especially in the late stages. As damage to your brain becomes more widespread, even simple actions like trying to understand what’s happening around you become exhausting. As a result, you sleep more, even during the day.

What is the top predictor of Alzheimer's?

Although age isn’t the cause of Alzheimer’s, it’s the strongest risk factor for the disease. After age 65, your risk of Alzheimer's doubles every 5 years. Another strong indicator that you could get the disease is a history of Alzheimer’s in your family.