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How Long Does It Take For Low Dose Naltrexone To Work?

How Long Does It Take For Low Dose Naltrexone To Work?

Low-dose naltrexone is an emerging treatment for many conditions. Read on to learn more about it.

Naltrexone is an FDA-approved treatment for opioid and alcohol use disorder. It has helped millions of people worldwide overcome substance use disorders.

Yet, recent studies suggest that low-dose naltrexone can also treat many other conditions. This article discusses what low-dose naltrexone is, how long it takes to work, and its benefits. 

What is Naltrexone, and How Does it Work?

Naltrexone is an opioid antagonist. This means it occupies opioid receptors to prevent opioids and endorphins from binding to them. As a result, opioids (and alcohol) can not produce feelings of euphoria.

At the same time, naltrexone reduces cravings for alcohol by suppressing the desire for food in the brain. This is also why doctors can use naltrexone to treat obesity

What is the Regular Naltrexone Dose?

Naltrexone is available in two forms:

  • Oral tablets
  • Depots that healthcare providers can inject into the muscles.

The naltrexone dose varies depending on the formulation. For the oral form, doctors recommend a starting dose of 25 mg. This is then increased gradually, up to a maximum of 150 mg taken in 2-3 divided doses daily, based on the patient's response.

Alternatively, providers administer the 380 mg depot form once a month.

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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. 

Pain

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. 

Cholestatic Pruritus

Studies show naltrexone can reduce symptoms of cholestatic pruritus in 50% of patients. 

Obesity

LDN users report up to a 10% body weight loss. This is because LDNs can suppress the body’s feeding and craving centers. 

Autoimmune Disorders

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

Depression

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.

Cancer

Some laboratory tests show that LDN can be an effective cancer treatment option. But no large human trials evaluating this effect exist. 

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What are the Side Effects of Low Dose Naltrexone?

Low-dose naltrexone, like any other medication, is not free from side effects. Luckily, most LDN side effects are mild and subside on their own.

LDN side effects include:

low dose naltrexone side effects

How to Prevent LDN Side Effects?

Fortunately, given the low doses, LDN side effects are rare. In addition, doctors recommend taking plenty of fluids and avoiding alcohol while taking LDN to minimize the risk of side effects further.

Will Low Dose Naltrexone Show up on a Drug Test?

LDN is not an opioid, so it will not appear on standard drug tests. But, LDN can show up on more comprehensive drug tests.

Medication-Assisted Treatments (MAT) at Confidant Health

Confidant Health specializes in treating substance use disorders by combining medications and behavioral therapies to deliver amazing results. Our virtual providers stay on top of any recent developments, such as the emergence of LDN, so that you can get the best care possible. Get in touch with us today!

This article has been medically reviewed by
Erin Hillers
Erin Hillers
Erin Hillers
Nurse Practitioner

Erin is a Nurse Practitioner with 8 years of experience in midwifery and women's health. She has spent the past 5 years specializing in the treatment of opioid and alcohol use disorders.

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