From the Guidelines
Drowsiness is not a commonly reported side effect of low-dose naltrexone (LDN) in the provided evidence, but it may still occur in some patients. When considering the potential side effects of LDN, it is essential to look at the most recent and highest quality studies. According to the study published in 2017 1, common side effects of LDN include headache, tachycardia, and vivid dreams, but drowsiness is not explicitly mentioned. However, the study published in 2022 1 discusses the use of naltrexone-bupropion ER for obesity and mentions that the second dose should not be taken late in the day to minimize the risk of insomnia, implying that naltrexone may have some impact on sleep patterns. Key points to consider when evaluating the potential for drowsiness as a side effect of LDN include:
- The dosage and administration schedule of LDN, as taking it at bedtime may help minimize potential drowsiness
- The individual patient's response to the medication, as some may be more prone to drowsiness than others
- The potential for LDN to influence sleep-wake cycles and energy levels due to its action on opioid receptors. It is crucial for patients to discuss any concerns about drowsiness or other side effects with their healthcare provider, who can provide personalized guidance and recommendations.
From the FDA Drug Label
Although no causal relationship with naltrexone hydrochloride is suspected, physicians should be aware that treatment with naltrexone hydrochloride does not reduce the risk of suicide in these patients In an open label safety study with approximately 570 individuals with alcoholism receiving naltrexone hydrochloride, the following new-onset adverse reactions occurred in 2% or more of the patients: ... somnolence (2%) The following events occurred in less than 1% of subjects: ... Psychiatric: ... somnolence Postmarketing ExperienceData collected from postmarketing use of naltrexone hydrochloride show that most events usually occur early in the course of drug therapy and are transient... Events that have been reported include ... somnolence
Drowsiness is a potential side effect of naltrexone, as somnolence (which is another term for drowsiness) has been reported in patients taking the medication, including at a rate of 2% in an open-label safety study in individuals with alcoholism, and in less than 1% of subjects in other studies 2.
From the Research
Drowsiness as a Potential Side Effect of Low-Dose Naltrexone
- Drowsiness has been reported as a side effect of low-dose naltrexone in several studies 3, 4, 5.
- In a study evaluating the effectiveness of low-dose naltrexone for chronic pain management, 32% of patients reported adverse effects, including drowsiness 3.
- Another study examining the side effects of low-dose naltrexone in patients with gastrointestinal disorders found that 61.2% of patients experienced side effects, with 32.4% having short-lived symptoms, including drowsiness 4.
- A study on the dose-ranging kinetics and behavioral pharmacology of naltrexone and acamprosate reported somnolence (drowsiness) as a side effect of naltrexone administration 5.
- However, it is essential to note that the frequency and severity of drowsiness as a side effect may vary depending on the individual, dosage, and specific condition being treated.