Everyone may feel sad occasionally, but the feelings don’t typically last long and pass within a couple of days.

When a person is depressed, it can affect daily life and normal functioning, causing pain for the person with depression as well as family and friends. Doctors refer to this condition as “depressive disorder” or “clinical depression.”

As people age, there are important life changes that can cause stress, sadness and uneasiness. The death of a loved one, retiring from work, or dealing with a serious illness can leave people feeling sad or anxious. Many older adults can go through a period of readjustment and regain their emotional balance, but some don’t and may develop depression.

According to the National Institute of Mental Health (NIH), depression is a common problem among older adults, but is not a normal part of aging. In fact, studies show that most older adults feel satisfied with their lives, despite having physical ailments.

When older adults suffer from depression, it may be overlooked, says the NIH, because they may be less willing to talk about their feelings of sadness or grief, or they may show different, less obvious symptoms, and doctors may be less likely to suspect or spot it.

It can be difficult to distinguish grief from major depression. Grief after losing a loved one is a normal reaction to the loss, but doesn’t generally require professional treatment. Grief that lasts for a very long time following a loss may require treatment.

The NIH states that it is widely believed that suicide more often affects young people, but older adults are also affected. Adults age 65 and older have a suicide rate that is higher than the national average. White men age 85 and older have the highest suicide rate in the U.S., according to NIH.

While there are many symptoms associated with depression, the common symptoms are feeling nervous or emotionally “empty;” feelings of excessive guilt or worthlessness; tiredness or a “slowed down” feeling; restlessness and irritability.

Other symptoms include feeling that life is not worth living; sleep problems (trouble getting to sleep, sleeping too much or wakefulness in the middle of the night); eating more or less than usual; loss of interest in once pleasurable activities; frequent crying; difficulty focusing or making decisions; and thoughts of death or suicide, or a suicide attempt.

The first step for getting appropriate treatment is to visit a doctor.

If people are in a crisis or thinking about harming themselves or attempting suicide, they are urged to tell someone who can help immediately, call a doctor, call 911, or go to the nearest emergency hospital. The toll-free number for the 24-hour hotline of the National Suicide Prevention Lifeline is (800) 273-8255; TTY: 1-(800) 799-4889 to be connected to a trained counselor at a suicide crisis center nearby, states the NIH.