Drugs to Avoid on LDN

On October 7, 2012, I retrieved information regarding Drugs to Avoid When Taking Low Dose Naltrexone. Please refer to the original site to see if there is more updated information.


If the site is no longer up, this is the information, verbatim, as last updated on that site on July 7, 2009.
* * * *
In general, Low Dose Naltrexone (LDN) should not be taken concurrently with opioid-containing drugs, immunosuppressive drugs, or immunomodulator drugs.

Do not take Naltrexone with any of the following without first consulting your doctor:

• disulfiram (Antabuse®);

• thioridazine (Mellaril®);

• buprenorphine (Buprenex®, Subutrex®);

• codeine (Tylenol with Codeine®, and other brand names);

• hydrocodone (Lorcet®, Lortab®, Vicodin®, Vicoprofen®, and other brand names);

• hydromorphone (Dilaudid®);

• levorphanol (Levo-Dromoran®);

• meperidine (Demerol®);

• methadone (Dolophine®, Methadose®);

• morphine (Kadian®, MS Contin®, MSIR®, OMS®, Roxanol®, Oramorph SR®, and other brand names);

• oxycodone (M-Oxy®, OxyContin®, OxyIR®, Roxicodone®, Percocet®, Percodan®, and other brand names);

• oxymorphone (Numorphan®);

• propoxyphene (Darvon®, and other brand names).






Chemotherapeutic agents (including Cellcept®)

Cautionary warnings

Because LDN blocks opioid receptors throughout the body for three or four hours, people using medicine that is an opioid agonist, i.e., a narcotic (such as morphine, Percocet®, Duragesic Patch® or codeine-containing medication) should not take LDN until such medicine is completely out of one’s system. Patients who have become dependant on daily use of narcotic-containing pain medication may require 10 days to 2 weeks of slowly weaning off of such drugs entirely (while first substituting full doses of non-narcotic pain medications) before being able to begin LDN safely.

There are some who believe steroids, chemotherapeutic agents, and other immunosuppressive medications are compatible with LDN. There are others, however, who would disagree. One example is Dr. M.R. Lawrence, an English physician with multiple sclerosis who treats his condition with LDN. This is his advice regarding drugs to avoid when taking LDN:

Because LDN stimulates the immune system and many of the drugs routinely used by the NHS in the treatment of MS [and other conditions] further suppress the immune system, LDN cannot be used in company with steroids, beta interferon, methotrexate, azathioprine or mitozantrone or any other immune suppressant drug. If there is any doubt, please submit [to your doctor] a full list of the drugs you are presently taking so that their compatibility may be assessed.

Dr. Lawrence has suggested a non-steroidal protocol for treating MS exacerbations. For more information, visit


Analgesics approved for use with LDN include Moxxor, aspirin, Tylenol®, Advil®, Motrin®, Aleve®, Naprosyn®, Ansaid®, Dolobid®, Orudis®, Voltaren®, Feldene®, Mobic®, and the food supplement, DL-Phenylalanine (DLPA). DLPA, which is also said to enhance the effectiveness of LDN, should be taken twice a day on an empty stomach in doses of 500 mg. It should not, however, be used by people with high blood pressure. For additional precautions, visit


Drugs That May Interact With Low Dose Naltrexone – Generic Name (Brand Name*)

Mixed Opiate Agonists/Antagonists

Buprenorphine (Buprenex®, Suboxone®, Subutex®)

Butorphanol (Dorolex®, Stadol®)

Nalbuphine (Nubain®)

Pentazocine (Naloxone®, Talwin®)

Opiate Agonists

Alfentinil (Alfenta®)

Clonidine (Catapres®)

Codeine (N/A)

Dronabinol THC (Marinol®)

Fentanyl (Duragesic®, Aqtic®, Sublimaze®, Fentora®)

Hydrocodone (Lorcet®, Lortab®, Vicodin®)

Hydromorphone (Dilaudid®

Levorphanol (Levo-Dromoran®

Meperidine (Demerol®, Meperitab®)

Methadone (Dolophine®, Methodose®)

Morphine (Kadian®, MSContin®)

Oxycodone (Percocet®, Endocet®, Roxicodone®, Endocodone®)

Oxymorphone (Opana®, Numorphone®)

Propoxyphene (Darvocet®, Darvon®)

Remifentinil (Ultiva®)

Sufentinil (Sufenta®)

Tramadol (Ultram®)

Other Medications

Disulfuram (Antabuse®)

Dronabinol THC (Marinol®)

Nabilone (Cesamet®)

Thioridazine (Mellaril®)

Clonidine (Catapres®)

* May not include each brand name available on the market in the United States


Clinical Pharmacology Online at


Accessed 06/14/07

Although Dr. Bihari is retired, you can speak to an associate knowledgeable about LDN by calling 212-929-4196
* * * *