An exploratory qualitative study of polydrug use histories among recently initiated injection drug users in San Juan, Puerto Rico.

It is well documented that drug users often modulate the effects of their primary drugs of use (e.g., cocaine) by using other drugs (e.g., alcohol), yet the effect of modulating and primary drug interactions on transitions from one class of drugs to another and from noninjected drugs to injected drugs is not clear. This issue, which is critical for understanding polydrug abuse,1 is explored in formative research based on in-depth qualitative interviews conducted during 2003-2004 with 25 recently initiated drug injectors residing in San Juan, Puerto Rico. This study suggests that increased use of a primary drug (e.g., cocaine) was influenced by enhancing or attenuating drugs, which were used in a particular order (e.g., alcohol, heroin) reflecting effectiveness in modulating primary drugs at different use intensities, as well as by participants' perceptions of the relative dangers associated with different drugs. Neither availability nor access appeared to affect the order in which participants used modulating drugs.