relapsing

/rɪˈlæpsɪŋ/
adjective
  1. Tending to return to a previous, usually worse, condition or state after a period of improvement.
    • Relapsing addictions often need long-term support to overcome.
    • The patient's relapsing symptoms made it hard to predict her recovery.
    • She has a relapsing form of the disease that requires ongoing treatment.