A drugs recall in Britain over fears thousands of anti-psychotic tablets could have been deliberately placed in packets of Nurofen Plus.
The mix-up is believed to have happened at a wholesaler and thousands of packs could be affected.
So far, three Nurofen Plus packets containing Seroquel XL have been found in pharmacies in south London.
Seroquel XL is a prescription-only, anti-psychotic drug used to treat several disorders including schizophrenia, mania and bipolar depression.
Nurofen Plus is for pain relief and contains codeine.