Smoking crack sends large quantities of the drug to the lungs, which creates an immediate and intense euphoric effect.
Studies indicate that elevated levels of serum C-reactive protein (CRP), a protein associated with inflammation, in cocaine abusers is associated with endothelial abnormalities and coronary artery calcification; factors known to contribute to heart disease.
THC levels in hashish can vary from almost none to 70%, and hash oil from 30-90%.
Many Ecstasy users have reported that the drug can provoke such a profound experience that it is not uncommon for addicted individuals to actively seek out and consume the drug regardless of the negative consequences.