Vraxoin

Vraxoin (also known as XYP) is a dangerous drug first shown in Nightmare of Eden. Vraxoin is a grey, ash-like powder which can be ingested orally. The drug causes slightly drunken affects and apathy, then causes extreme anger during withdrawal. The Doctor also said it lead to more extreme apathy after time.

Vraxoin is known to be made from dead Mandrels, though it's thought to have a rarer source.