Desperate to relieve his chronic back pain, an 80-something man bought herbal pills from a peddler.
But the capsules had high levels of dexamethasone, a potent steroid used for anti-inflammatory purposes, and he suffered a hormonal disorder.
He is now in intensive care fighting for his life.
The Health Sciences Authority (HSA) has issued an alert on illegal pain medication that contain high levels of the steroid after two people suffered serious side effects.
But many are still buying prescription and counterfeit drugs from unauthorised peddlers.