Description
Opioids are a class of drugs that include the illegal drug heroin, synthetic opioids such as fentanyl, and pain relievers available legally by prescription, such as oxycodone (OxyContin?), hydrocodone (Vicodin?), codeine, morphine, and many others. These drugs are chemically related and interact with opioid receptors on nerve cells in the body and brain.

Description
Herpes Labialis (Oral Herpes) is a type of herpes simplex occurring on the lip, i.e. an infection caused by herpes simplex virus (HSV). An outbreak typically causes small blisters or sores on or around the mouth. The sores typically heal within 2–3 weeks, but the herpes virus remains dormant in the facial nerves, following orofacial infection, periodically reactivating (in symptomatic people) to create sores in the same area of the mouth or face at the site of the original infection.