|MadSci Network: Neuroscience|
Opioids include opium, morphine, heroin, and codeine; the synthetic drugs include Demerol and methadone. All of these relax the central nervous system and have similar sleep-inducing and analgesic (pain-relieving) effects. Heroin is the most commonly abused opioid drug in the United States; there are an estimated 400,000 to 600,000 heroin addicts in the U.S. alone. Heroin and Morphine are used as painkillers. These drugs block the pain receptors in the brain so that people do not feel pain. They also produce mental clouding, drowsiness, and euphoria.
Like many drugs, opioids are metabolized by liver enzymes belonging to the Cytochrome P450 family. For example methadone, a synthetic opioid used for recovering heroin addicts, is metabolized by the 3A4 subtype of CYP450. This is relevant in terms of your question in that grapefruit is a well known inhibitor of this subtype and drugs metabolized by CYP450 3A4 would be expected to have an increase in their levels due to the inhibition of this enzyme which normally metabolizes the drug. Thus by eating foods which alter the metabolism of drugs, we can either increase or decrease their effects.
Hope this helps,
gabriel vargas md/phd
The Chemistry of Mind-Altering Drugs : History, Pharmacology, and Cultural Context by Daniel M. Perrine
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