When should I consider referring a patient with fatigue to a specialist for further evaluation?

You should consider referring a patient with fatigue to a specialist for further evaluation in several scenarios:

• Suspected or Confirmed Underlying Cause: Arrange referral to an appropriate secondary care specialist if there is a suspected or confirmed underlying cause for the fatigue that cannot be managed in primary care ¹.
• Chronic Fatigue Syndrome (CFS) / Myalgic Encephalomyelitis (ME): Arrange referral to a specialist chronic fatigue syndrome (CFS) service if the diagnostic criteria for CFS are met, symptoms have persisted for 3 months, and are not explained by another condition ¹.
• Persistent, Unexplained Fatigue (not meeting CFS criteria): Consider arranging referral to an appropriate specialist if there is persistent, unexplained tiredness/fatigue which does not meet the diagnostic criteria for CFS, if:
  • There is significant uncertainty regarding the presence of an underlying physical cause ¹.
  • The person would benefit from the reassurance of a second opinion or from a thorough specialist secondary care evaluation ¹.
  • The person may benefit from access to the care delivered by a specialist CFS service ¹.
  • A secondary care opinion is required for occupational reasons, or for assessment of eligibility for disability benefits ¹.
• Long COVID: Consider referring people to an appropriate service, such as an integrated multidisciplinary assessment service, any time from 4 weeks after the start of acute COVID-19, after ruling out acute or life-threatening complications and alternative diagnoses ³. This is particularly relevant if the person has multiple severe symptoms (especially if both physical and mental health are affected), profound functional impairment, symptoms significantly impacting daily activities, persistent symptoms following a severe acute illness, diagnostic doubt, or atypical symptoms ³.
• Multiple Sclerosis (MS) Related Fatigue: If a person with MS wishes to try a medicine for fatigue, refer them to a specialist to fully discuss the treatment options ⁶.
• Suspected Cancer: While fatigue itself does not always trigger a direct specialist referral, it can be a symptom that prompts urgent primary care investigations for suspected cancer, which may then lead to a suspected cancer pathway referral ⁷. For example, consider an urgent chest X-ray for unexplained fatigue in those aged 40 and over with a smoking history or asbestos exposure (for suspected lung or mesothelioma) ⁷. For persistent fatigue in adults, consider a very urgent full blood count (within 48 hours) for suspected leukaemia ⁷. For unexplained fatigue in women, carry out primary care tests including measuring serum CA125 for suspected ovarian cancer ⁷.