Skin popping is a method of administration whereby drugs are injected or deposited under the skin. The drug then diffuses into the capillary networks where it enters circulation. It can include subcutaneous placement or intradermal placement though is also rarely used to mean intramuscular injection. Skin popping is distinct from intravenous use in that an intravenous injection deposits the drug directly into the blood stream. Higher potency prescription opioids, such as morphine, fentanyl, or meperidine can be injected subcutaneously, as can cocaine. Skin popping increases the duration of the high one gets from drugs such as cocaine. The sites where skin popping with cocaine has been performed have an area of central pallor surrounded by bruising (ecchymosis). This pattern is due to the vasoconstrictive properties of cocaine acting locally at the injection site with hemorrhage occurring in the surrounding tissue. Skin popping puts one at risk for developing secondary amyloid associated (AA) amyloidosis. Tetanus has also been associated with skin-popping as has botulism.