How Long Does Naltrexone Stay in Your System?
The half-life refers to the time it takes the concentration of a drug in the blood to reduce by half. The body eliminates 97% of any medication after a duration equal to 5 half-lives.
The naltrexone half-life varies depending on its formulation. The half-life of the pill form is between 4-6 hours. This means the body takes 20-30 hours to eliminate it.
In contrast, the half-life of the depot formulation is 5-10 days. This means it can remain in the system for 25-50 days.
Please remember that researchers base these values following tests on many 'healthy' individuals. Many factors, including liver and kidney health, genetics, and muscle mass, can affect the half-life of a drug and so how long it remains in the system. Thus, always consult a healthcare professional before starting any treatment.
What is Low Dose Naltrexone?
Low-dose naltrexone (LDN) refers to the off-label use of naltrexone in less than regular doses. While its mechanism of action remains unknown, researchers believe LDN works in three main ways:
- By triggering the release of 'feel good' hormones in the brain
- By limiting the production of inflammatory chemicals in the body
- By regulating natural opioid production
How is LDN Dosed?
Dosing LDN is not an exact science and varies based on the user's response. Doctors initially prescribe the lowest available dose (0.5mg) of naltrexone at bedtime for several weeks. This is then gradually increased to a maximum of 5mg over 1-3 months, depending on how the patient responds.
How Long Does it Take Low Dose Naltrexone to Work?
LDN takes a few weeks (between 4 and 6) to work. This is why doctors initially recommend using the lowest dose for a few weeks before increasing the quantity. In most cases, users can experience LDNs maximum effect after 12 weeks.
If you do not notice any improvement after six weeks of treatment, please consult your doctor about other options.
What is Low Dose Naltrexone Used For?
Studies show promising results with LDN in many conditions. These include:
Fibromyalgia and Chronic Fatigue Syndrome
Fibromyalgia patients in two prospective studies reported better symptom control and quality of life. Research in chronic fatigue syndrome patients shows similar improvements.
According to recent studies, LDN shows promise as a treatment for chronic pain.
LDN can reduce the production of inflammatory substances while increasing the release of endorphins (feel-good hormones). This helps relieve pain.
Studies show naltrexone can reduce symptoms of cholestatic pruritus in 50% of patients.
LDN users report up to a 10% body weight loss. This is because LDNs can suppress the body’s feeding and craving centers.
Studies conducted by Regis University School of Pharmacy (Colorado) show LDN to be an effective treatment option for autoimmune conditions such as
- Crohn's disease
- Multiple sclerosis (MS)
- Rheumatoid arthritis
In small clinical trials, patients with a history of relapsing depression report improvements in mood with LDN.
Post-Traumatic Stress Disorder (PTSD)
PTSD patients report reduced self-destructive impulses and better symptom control when taking LDN.
Some laboratory tests show that LDN can be an effective cancer treatment option. But no large human trials evaluating this effect exist.