Fentanyl is a potent opioid prescribed to treat severe pain. The fentanyl patch delivers a steady dose of medication through your skin for lasting pain relief. Grapefruit juice inhibits an enzyme responsible for metabolizing fentanyl, which can lead to dangerous levels of the medication in your bloodstream. To prevent potentially fatal side effects, do not use fentanyl unless it was prescribed to you by a doctor.
Pharmacology
A synthetic opioid analgesic, fentanyl is active in microgram doses and is often administered transdermally via a patch that is worn on your skin. Like other opiates, fentanyl acts on your brain to produce its effects, which include reduced pain, coughing and fever. Like other central nervous system depressants, it slows bodily functions such as breathing and heart rate, which can be dangerous in the event of an overdose.
Side Effects/Interactions
Fentanyl may be deadly when combined with certain drugs, supplements or foods. Duragesic -- a company that manufactures fentanyl patches -- states on their website that drinking grapefruit juice while wearing the Duragesic patch can lead to dangerously high levels of fentanyl in your blood, increasing your risk of overdose. Grapefruit juice inhibits an enzyme known as cytochrome P450 3A4 that is involved in the metabolism of fentanyl and many other drugs. Other cytochrome P450 3A4 inhibitors such as ketoconazole, fluconazole and ritonavir have similar effects and should not be combined with fentanyl. Symptoms of overdose like slowed breathing, extreme dizziness and weak pulse may occur when you combine grapefruit juice with fentanyl, according to Drug Information Online.
Prevention/Solution
Avoiding grapefruit and grapefruit juice while using the fentanyl patch can help you prevent a potentially fatal overdose. Follow instructions for usage carefully and never use fentanyl that was not prescribed to you by a doctor. Talk to your physician about which foods and medicines are safe to ingest while using the fentanyl patch. Reading food, drink and supplement labels can help you determine which substances contain grapefruit. If you accidentally ingest grapefruit juice while wearing the fentanyl patch, seek medical attention immediately.
Considerations
Like other opiates, fentanyl can be habit-forming and may cause physical dependence. Attempting to increase the potency of fentanyl by combining it with grapefruit juice can be fatal. Combining alcohol and other depressants with fentanyl can have additive effects that increase your likelihood of respiratory depression and death. To prevent withdrawal symptoms, don't stop using fentanyl abruptly.
