Naltrexone HCL, while effective, can cause side effects. These vary in severity and frequency. Commonly reported side effects include nausea, vomiting, abdominal cramps, dizziness, headache, and fatigue. These typically lessen with continued use, but if severe, contact your doctor.
Gastrointestinal Issues
Upset stomach is a frequent complaint. Consider taking Naltrexone with food to mitigate this. If nausea or vomiting is persistent, discuss alternative medication administration options with your healthcare provider. They might suggest a lower starting dose or a different medication.
Liver Function
In rare instances, Naltrexone can affect liver function. Regular liver function tests are recommended, especially during initial treatment. Report any signs of liver problems, such as yellowing of the skin or eyes (jaundice), dark urine, or persistent fatigue, immediately to your doctor.
Other Potential Side Effects
Less common side effects include anxiety, depression, insomnia, and changes in libido. While rare, serious allergic reactions are possible. Stop taking Naltrexone and seek immediate medical attention if you experience symptoms such as difficulty breathing, swelling of the face, lips, tongue, or throat, or hives.
Summary of Potential Risks
| Gastrointestinal | Nausea, vomiting, abdominal pain | Take with food, inform your doctor if severe |
| Central Nervous System | Headache, dizziness, fatigue, anxiety, insomnia | Inform your doctor; adjustments to dosage may be needed |
| Hepatic | Abnormal liver function tests, jaundice | Seek immediate medical attention |
| Allergic Reactions | Difficulty breathing, swelling, hives | Stop medication, seek immediate medical attention |
Interactions with Other Medications
Naltrexone can interact with other medications. Always inform your doctor and pharmacist of all medications, supplements, and herbal remedies you are taking. This includes over-the-counter drugs. Failure to disclose medication use can lead to dangerous interactions.
