The Most Dangerous Interaction: Opioids
Naltrexone is a powerful opioid antagonist, which means it works by binding to and blocking opioid receptors in the brain. This action prevents opioids from producing euphoric and sedative effects. The most critical and life-threatening interaction is taking naltrexone while opioids are still in your system or attempting to use opioids while on naltrexone treatment.
Precipitated Opioid Withdrawal
If a person is physically dependent on opioids and takes naltrexone, the medication will rapidly displace the opioids from their receptors. This can trigger a sudden and severe withdrawal syndrome known as "precipitated withdrawal". The symptoms are significantly more intense and rapid-onset than typical opioid withdrawal and can be extremely dangerous, sometimes requiring hospitalization. To avoid this, a patient must be completely opioid-free for a specified period—typically 7 to 10 days for short-acting opioids and longer for extended-release or longer-acting opioids like methadone. A doctor will often perform a naloxone challenge test or urine screen to confirm the absence of opioids before starting naltrexone.
The Risk of Overdose
Another severe risk is the attempt to overcome naltrexone's opioid-blocking effect by taking very high doses of opioids. This is extremely dangerous and can lead to serious injury, coma, or death. Naltrexone also lowers a person's tolerance to opioids during periods of abstinence. If a patient stops naltrexone treatment and relapses to opioid use, they are at a much higher risk of a fatal overdose, even with a dose lower than what they previously used.
Common Opioids and Illicit Substances to Avoid
- Heroin
- Morphine
- Codeine
- Oxycodone (OxyContin, Roxicodone)
- Hydrocodone (Vicodin, Hysingla ER)
- Fentanyl
- Tramadol (Ultram)
- Methadone
- Buprenorphine
Naltrexone and Alcohol
Naltrexone is also used to treat alcohol use disorder by blocking the pleasurable, reinforcing effects of alcohol. Unlike Disulfiram (Antabuse), it does not cause a violently ill reaction if you drink while on the medication. However, mixing alcohol with naltrexone is still not recommended for several reasons:
- Continued Intoxication: Naltrexone does not prevent the cognitive and motor impairment associated with alcohol consumption. You can still become intoxicated, have poor judgment, and experience a loss of coordination, making activities like driving unsafe.
- Liver Strain: Both naltrexone and heavy alcohol consumption can impact liver function. Combining the two can place additional strain on the liver, especially if there is pre-existing liver disease.
- Undermined Recovery: Drinking while on naltrexone can undermine the recovery process, even if the euphoric feeling is blocked. The goal of treatment is to reduce cravings and establish new behaviors, and consuming alcohol can hinder that progress.
Sedatives, Depressants, and Hidden Opioids
Certain other medications and substances can interact with naltrexone, with varying degrees of risk. It is crucial to inform your doctor of all medications, including over-the-counter drugs and supplements, before starting treatment.
Medications that Contain Opioids
Some prescription and over-the-counter medications for common ailments like coughs, colds, and diarrhea contain opioids. Taking these while on naltrexone can cause precipitated withdrawal. Always check with a pharmacist or doctor before taking a new medication. Examples include some cough syrups containing codeine and certain antidiarrheals like diphenoxylate/atropine (Lomotil). Loperamide (Imodium) also works similarly to an opioid and should be used with caution.
Benzodiazepines and Other CNS Depressants
Benzodiazepines (like Xanax, Klonopin, and Ativan) are central nervous system (CNS) depressants. While there is no known direct interaction with naltrexone's mechanism, combining them with naltrexone can potentially increase the risk of side effects like excessive drowsiness, dizziness, and impaired coordination. Combining these substances with alcohol can be especially dangerous due to cumulative CNS depression.
Other Notable Interactions
Other substances like cannabis and CBD products might also interact, potentially increasing the effects of the cannabis product. There are also potential interactions with medications for alcohol use disorder like disulfiram, which can increase the risk of liver damage when combined with oral naltrexone.
Substance Interaction Risks with Naltrexone
| Substance Category | Interaction Risk | Primary Danger When Mixed with Naltrexone |
|---|---|---|
| Opioids (Prescription & Illicit) | VERY HIGH | Severe precipitated withdrawal; risk of fatal overdose if attempting to override the block |
| Alcohol | MODERATE | Impairment and intoxication without euphoria; potential increased liver strain with heavy use |
| Benzodiazepines | CAUTION | Increased sedation, dizziness, and impairment |
| Other CNS Depressants | CAUTION | Enhanced sedative effects; cumulative CNS depression, especially with alcohol |
| Opioid-Containing Medicines | HIGH | Potential for precipitated withdrawal from hidden opioid ingredients in cough or cold remedies |
Crucial Safety Precautions
For safe and effective treatment with naltrexone, patient adherence and careful communication with healthcare providers are essential. Always carry medical identification stating that you are on naltrexone. Inform all doctors, dentists, and emergency personnel about your medication to ensure proper pain management and care. Adhering to these safety protocols is a cornerstone of a successful recovery journey.
Conclusion
Understanding what to avoid while taking naltrexone is a matter of safety, not just efficacy. The most significant danger lies in the interaction with opioids, which can cause life-threatening precipitated withdrawal and overdose. While alcohol does not produce the same acute reaction, it can still cause impairment and liver issues, while undermining the therapeutic goal of the medication. Interactions with other CNS depressants and hidden opioids also present notable risks. By following a doctor's guidance, being aware of potential interactions, and transparently communicating about all substances used, patients can safely and effectively use naltrexone as a tool for recovery. For more information on medication-assisted treatment, resources from the Substance Abuse and Mental Health Services Administration (SAMHSA) can provide further guidance.
