Levamisole, which is a common adulterant of cocaine, can cause an ANCA positive vasculitis. This is an indirect effect of the drug, not strychnine or any other adulterant. It also reported that BZP was being used as an adulterant in illicit drugs. It has been found as an undeclared adulterant in supposedly "natural" health supplements. An adulterant is distinct from, for example, permitted food additives. Diazepam has been found as an adulterant in heroin. On March 30 Silva released a statement admitting using a urine adulterant. Xylazine has similar behavioral consequences as heroin, thus it is commonly used as an adulterant. They have also been used as an adulterant for coffee. It has been used as an adulterant in cocaine resulting in serious side effects. It has been found as an adulterant in some dietary supplements. Infrequently, MDEA is an adulterant of ecstasy pills. Octodrine has also been found as an adulterant in sports supplements. The leaves resemble tea leaves, and were used as an adulterant of tea. It is an adulterant of the more costly myrrh.