We could speculate...
1. Long-Term Cocaine Effects
As cocaine abuse continues and tolerance builds, users begin to experience long-term cocaine effects. Cocaine is a highly addicting drug, which can lead to enormous medical complications, including heart disease, respiratory failure, strokes, seizures and various gastrointestinal complications
2. Opiates cause severe constipation and possibly bowel obstruction..
But it could be totally unrelated and we don't really know.