Intravenous drug abuse may lead to fillers and adulterants like talc lodging in the blood vessels of the lung; the deposits are especially visible under polarized light.

Semi-synthetic opioids like oxycodone, fentanyl, hydrocodone, hydromorphone, and methadone are derivatives of thebaine, a component of the poppies from which opium is produced. Introduced in 1917 as painkillers, the abuse of opioids is now a public health issue of epidemic proportions.

Chronic intravenous use of prescription medications formulated for oral administration can be diagnosed through histologic examination of the lungs. Prescription medications in tablet form are comprised of an active ingredient and bulking agents such as cellulose, starch, or magnesium trisilicate (better known as talc). Introduction of crushed prescription medications dissolved in water into the vascular system may cause pulmonary deposition of fillers within the spaces around the blood vessels and the formation of granulomas (a collection of immune cells that attempts to wall off foreign material). Although such
granulomas are commonly found in the lungs of prescription drug abusers, they are rarely symptomatic. Polarized lights highlights birefringent crystals that may identify the foreign material present: starch generates bright patterns in a Maltese cross formation, while talc deposits cause needle-shaped or plate-like crystals. Identification of foreign material around the blood vessels within the lung indicates chronic intravenous substance abuse.