Why depression makes you tired and how to deal with fatigue

Fatigue is one of the most common symptoms of depression.
If you are depressed, it’s likely that you will lack energy and feel tired physically, emotionally, and cognitively.
Depression can also make sleep less restful and restorative – here’s how to get better sleep and feel less tired.
This article was medically reviewed by David A. Merrill, MD, PhD, psychiatrist and director of the Pacific Brain Health Center at Pacific Neuroscience Institute at Providence Saint John’s Health Center.
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For people with depression, feeling tired is an all-too-common symptom. “Tiredness or fatigue is one of the hallmarks of depression,” says Amy Ricke, MD, of Your Doctors Online.

With depression, energy levels dip, and many of the symptoms, such as profound sadness and loneliness, can further exacerbate fatigue. Here’s why depression makes you tired, how to tell if it’s the cause of your fatigue, and how you can feel more refreshed and well-rested.

Depression acts on neurotransmitters to make you tired

Depression is likely associated with changes in brain neurotransmitters, such as dopamine, norepinephrine, and serotonin. “These neurotransmitters play important roles in regulating energy levels, sleep, appetite, motivation, and pleasure,” Ricke says.

According to Harvard Health Publishing, depression is a complex disease with many possible and interlinked causes, including genetics, medical conditions, stressful life events, and brain chemistry. And it can be challenging to tell the difference between everyday tiredness and depression-related fatigue.

"Fatigue and depression can look quite similar," says Alex Dimitriu, MD, psychiatrist and sleep medicine expert, and founder of Menlo Park Psychiatry & Sleep Medicine.

How to tell if you are depressed or just tired

With both depression and fatigue, symptoms include low energy, low motivation, and anhedonia, or a loss of interest in pleasurable activities, Dimitriu says.

One distinguishing factor can be the desire to engage in activities - people who have fatigue wish to do things, but lack energy, whereas people with depression have lower interest in activities, he says.

"Another important consideration is the duration of the low mood and if it improves with sleep," Dimitriu says. A single good night's sleep can improve a tired person's mood, he notes.

But depression-related fatigue permeates every facet of a person's life, says Ricke. The effect is felt:

Physically: Everyday tasks - eating, showering, getting dressed, and so on - may become difficult. "The body can feel heavy, slow, and stiff due to depression," Ricke says.
Cognitively: Due to depression, you may experience "difficulty sustaining focus, concentrating, and processing information," Ricke says. Of course, lack of sleep can have a similar cognitive impact, making it challenging to concentrate.
Emotionally: Here is where the effects may be most profound. "Fatigue makes it more difficult to weed through the already confusing thoughts and feelings that are part of depression," Ricke says. Forming emotional connections with friends, family, and the people around you may be more challenging when you're fatigued, she says. And that, in turn, "can perpetuate feelings of aloneness and hopelessness," Ricke says.

Depression also affects your ability to sleep

Adults should sleep seven hours a day or more, per the Centers for Disease Control and Prevention. For people with depression, that task may be challenging.

"People with depression often have trouble falling asleep or difficulty staying asleep, or both," says Dimitriu. People with depression may experience less slow wave - or deep - sleep, according to a September 2014 review in the journal Sleep Science. The end result? Sleep feels "less restful and restorative," says Ricke.

Plus, people who are depressed can engage in "maladaptive behaviors that contribute to poor sleep," says Ricke. For instance, depression-related fatigue can lead to someone taking a nap, which will only make falling asleep in the evening harder, she says.

Dimitriu and Ricke note that staying active may be hard for someone with depression, but resisting the temptation to stay on the couch can go a long way - in fact, getting some physical activity each day may even help you sleep better at night.

How to sleep with depression

You can try these strategies to improve the quality of your sleep, especially if you've been having difficulty with a mental illness.

Have a schedule: "Try to fall asleep and get up around the same time each day," advises Ricke. Not following a sleep routine is linked with obesity, hypertension, and other poor health outcomes, per a 2018 study in Nature. Plus, following a schedule makes it easier for you to fall asleep and wake up each day, per the National Sleep Foundation.
Keep screens out of the bedroom: Don't use your phone as an alarm clock, or scroll through social media before going to sleep. Be screen-free for an hour prior to bedtime, says Ricke. "The light from screens can interfere with the body's natural production of melatonin which helps with sleep," she says.
Schedule morning exercise: Working out early in the day helps with mood and sleep, Ricke suggests, but avoid high-intensity nighttime workouts, which may interfere with rest.
Avoid caffeine and alcohol: Stay away from caffeine, which will keep you up. Also avoid alcohol, which "will inevitably worsen both sleep and depression," says Ricke.
Talk to your doctor: If the above strategies do not make a difference, make an appointment - your doctor can help confirm there isn't another issue interfering with your sleep, notes Ricke. "Fatigue can be a symptom of untreated or partially treated depression, or it can be a medication side effect," she adds, so reach out if you are on antidepressants or any other medication.