These PET scans show the normal distribution of opioid receptors in the human brain. A new study suggests ketamine may activate these receptors, raising concern it could be addictive.
Philippe Psaila/Science Source
George McCann has been diagnosed with a subtype of bipolar disorder called the "fear of harm" profile, and finds that a prescribed dose of ketamine every few days alleviates his symptoms.
Michael Rubenstein for NPR