Why does generalised anxiety disorder cause fatigue?

Fatigue is a common presentation of Generalised Anxiety Disorder. Remaining prepared for something to go wrong can keep muscles tight and thoughts active for long stretches. Sleep may be shorter, lighter, or interrupted, leaving you without the sense of recovery you expect by morning. Anxiety can also make ordinary decisions and social interactions feel more effortful. Fatigue does not necessarily match how much physical activity you have done, and it can fluctuate with worry, sleep quality, appetite, and daily demands.

Plan essential tasks for the part of the day when your energy is strongest, and alternate demanding activity with quiet recovery rather than pushing through until you crash. Regular meals, fluids, gentle movement, and a steady sleep routine can support energy. Keep notes on sleep, mood, stressors, and any new symptoms. A healthcare professional can assess anxiety treatment options and consider other contributors to fatigue, including illness, medication effects, sleep disorders, and low mood.

Arrange a medical review if fatigue is ongoing, worsening, affecting your work or self-care, or occurring with unexplained weight change, persistent fever, or new pain. Seek urgent help for chest pain, severe breathlessness, fainting, confusion, or thoughts of harming yourself. These symptoms require assessment rather than being attributed to anxiety alone.

Ask whether the pattern of fatigue could relate to anxiety, sleep, mood, medicines, or a physical condition. Tell the clinician when it started, what makes it better or worse, how you sleep, and how it affects everyday activities.