Is there a difference in safety between a low dose naltrexone pregnancy and naltrexone in pregnancy with the standard 25 mg or 50 mg dose?
Naltrexone HCL is a drug with many uses. Naltrexone hydrochloride is used to treat opioid dependence and other forms of addiction, including alcohol addiction, and binge eating.
Low dose naltrexone, or LDN, has many other uses. It is used to treat various pain syndromes, often related to autoimmune conditions.
Additionally, there are claims that LDN may have many other uses. LDN is prescribed in dosages ranging from 1-5 mg, rather than 50 mg.
In order for a patient to get LDN at a pharmacy, they often have to visit a compounding pharmacy that can custom make it for them. Another form of LDN is known as ultra low dose naltrexone, or ULDN, which is naltrexone in even lower dosages.
For medication assisted treatment for opioid addiction, a patient may be given the Vivitrol shot which provides naltrexone coverage for a month. For alcoholism, the patient may be prescribed a daily naltrexone tablet.
Another option is the surgical placement of naltrexone implants, which can last for up to six months at a time. Naltrexone implants in the past had to be surgically removed, but new ones being studied in clinical trials will dissolve over time.
There has long been concern over the best way to medically treat opioid dependent pregnant women. The biggest concern is regarding naltrexone treatment and neonatal outcome.
There are few studies available that have evaluated the safety of naltrexone in pregnancy.
Of course the concern of risks to pregnant patients during prenatal care and danger to the fetus would likely be less with LDN and ULDN compared to the full dose of naltrexone pills or the vivitrol shot.
However, as with full dose naltrexone during pregnancy, the effects of low dose naltrexone during pregnancy are not fully understood. While there are many animal studies to document the effects of obstetric naltrexone, there are few human studies to provide adequate information.
One reason for interest in naltrexone treatment during pregnancy is to avoid neonatal opioid withdrawal syndrome. Pregnant patients who take either buprenorphine (Suboxone, Subutex, ZubSolv), or methadone do have a risk of their baby developing neonatal abstinence syndrome.
Neonatal abstinence syndrome is where the baby is born withdrawing from drugs taken by the mother before giving birth. While the risk is present, with buprenorphine, it is a minimal risk.
Doctors now have years of experience in maintaining patients on buprenorphine during pregnancy. Suboxone doctors and OB/Gyn doctors have worked well, coordinating care with excellent results.
While methadone was once considered to be the gold standard of medication assisted treatment throughout pregnancy, the new gold standard is clearly buprenorphine, often simply referred to as Subutex.
For patients taking Suboxone, which is naloxone combined with buprenorphine, they must be switched to the monoproduct, Subutex when they discover that they are pregnant. The buprenorphine and naloxone combination is not known to be safe during pregnancy.
When it comes to Suboxone vs Subutex in pregnancy, Subutex is the choice we go with, since we can not be certain of the safety of Suboxone when pregnant. Suboxone in pregnancy is not recommended.
Is naltrexone in pregnancy safe?
This is a good question. We do not really know for sure if taking naltrexone while pregnant is completely safe.
There is some evidence that naltrexone may have negative effects on the fetus. Animal studies have confirmed this, but there are no human studies.
One question we might ask is this. How is it that buprenorphine is safe and not naltrexone? The two drugs do have some similarities.
Both drugs are opioid receptor antagonists, meaning that they block opioid receptors. The main difference is that buprenorphine is also a partial agonist, activating the opioid receptor at the same time.
So, would buprenorphine cause the same issues with animal fetuses? I am not aware of studies that would confirm or refute this possibility.
Another issue to consider is how to handle the induction of medication for opioid use disorder for a woman who has just discovered that she is pregnant. Making the transition too stressful with excessive withdrawal symptoms may lead to a miscarriage.
One female patient once told me that she had multiple miscarriages over the years because she always tried to quit opioids right when she discovered that she was pregnant. The stress of opioid withdrawal seemed to be the cause of miscarriage.
With methadone use during pregnancy, going to a methadone maintenance clinic, the patient does not have to go through withdrawal, because methadone may be started the same day that the patient stops taking addicting street opioids.
This is the main advantage of methadone treatment. It can be started right away without having to wait for opioids to clear from the patient’s system.
Some people may think that methadone maintenance is outdated and a thing of the past, now that we have Suboxone treatment. Yet, with today’s long-lasting fentanyl analogs on the streets, methadone clinics have a renewed relevance in helping people smoothly transition off of fentanyl without risking precipitated withdrawal.
Unfortunately taking methadone while pregnant may put the patient at higher risk for neonatal abstinence syndrome, or neonatal withdrawal, after birth of the baby.
Buprenorphine is the better option in this case, and naltrexone possibly even better.
Buprenorphine can be started at about 24 hours after quitting street opioids in most cases. However, the fentanyl analogs that are replacing heroin on the streets may induce precipitated withdrawal, even at 24-48 hours or longer.
One solution to this issue is to use the Burnese Method, which is microdosing Suboxone or microdosing Subutex. The doctor starts the patient on a low dose of buprenorphine and gradually increases it, to avoid precipitated withdrawal.
What is the waiting period to start naltrexone after quitting opioid medication or street opioids?
Naltrexone requires a longer, more extensive opioid detoxification to avoid the adverse effects of precipitated withdrawal, which is opioid withdrawal symptoms caused by taking an opioid blocker too soon.
A patient suffering from drug addiction who is going to start addiction treatment with naltrexone must wait at least a week after quitting opioids to start the naltrexone shot or tablets. Imagine how unpleasant it will be for a pregnant woman to go through a week of opioid withdrawal, waiting to start naltrexone?
Maternal relapse on an opioid drug will be a high risk during this waiting period, and there is the risk of miscarriage or other adverse events, due to the stress of withdrawal. Additionally, when starting naltrexone therapy, there is still the risk for precipitated withdrawal because it is such a potent opioid antagonist.
One of the main concerns with drug detoxing while pregnant is to avoid the risk of relapse and opioid overdose.
While the safety of the fetus is still of utmost concern, if the mother relapses and overdoses, both the mother and fetus will be at risk for a tragic outcome.
In making a decision for benefits vs risks regarding thoughts about methadone while pregnant, Subutex while pregnant, or even naltrexone while pregnant, the most important consideration is to keep the mother opioid-free throughout and after the pregnancy.
Even when babies are born with neonatal withdrawal, they can be medically treated. The risk of this happening to a baby whose mother is taking buprenorphine is minimal.
What about LDN and pregnancy?
LDN is low dose naltrexone, which is typically used for conditions other than addiction therapy. However, what if a patient was given microdose naltrexone to avoid precipitated withdrawal?
Could there be a Burnese Method for naltrexone? I do not know if anyone has approached this idea or tried it with non-pregnant patients.
It would be interesting to see if patients on street opioids, or even methadone or buprenorphine could be gradually transitioned by using ultra low dose naltrexone (ULDN), and then low dose naltrexone, gradually introducing the opioid blocker into the system.
Naltrexone is unique amongst the prescription drugs used to treat opioid addiction. It is also used to treat alcohol dependence as well.
It happens to be the only one of the three approved drugs for opioid addiction treatment that is not an opioid and it is not controlled by the federal government.
While it is important to rule out liver disease before starting naltrexone therapy, it is otherwise known to be a very safe medication. In fact, there is a movement to make naltrexone an over-the-counter medication eventually.
There have also been recent studies on naltrexone implants that are very long-lasting.
These implants last for up to six months and then naturally dissolve.Unlike the Probuphine implant, that used buprenorphine, and was taken off the market recently, New experimental naltrexone implants do not need to be removed surgically.
If you listen to my podcast interview with Dr. Adam Bisaga, we discuss the many benefits of these new implants. Check out my naltrexone podcast for more information.
Imagine a naltrexone implant that lasts throughout a full term pregnancy. There would be little need to worry about issues of opioid cravings.
Naltrexone has been studied and found to be about as effective as buprenorphine in treating opioid addiction. The success rate is around 50%, which is fairly high when it comes to addiction treatment.
In order to consider such a treatment, I believe that we are going to need more information regarding the safety of naltrexone during pregnancy. We do know that naltrexone is far safer for the fetus than abuse of any street opioid would be.
The other issue, besides the safety of the drug, is how to start treatment if the patient is already pregnant. There are drugs that can treat withdrawal symptoms.
For example, there is Lucemyra, which is a medication uniquely indicated for treating opioid withdrawal symptoms. Currently, it is a very expensive medication, but it is effective in reducing symptoms and making opioid withdrawal more tolerable.
Why would people be so intent on figuring out how to use naltrexone for opioid addiction during pregnancy?
As mentioned above, naltrexone is the only approved drug for treating opioid addiction with medication assisted treatment that is not itself an opioid. This distinction means a lot to some people.
There are people who have a serious focus on the opioid status of buprenorphine. Even though Suboxone is an opioid, it is a unique opioid that should not be compared directly to other opioids.
The fact that buprenorphine is both an opioid antagonist, and partial agonist at the same time gives it special properties, including the ceiling effect. The ceiling effect means that buprenorphine rarely causes respiratory depression and overdose.
Additionally, for people who have an opioid tolerance already, it does not cause them to get high. Suboxone is only very rarely abused, because it tends to not get people high at all.
Still, there are people who only want to take non-controlled, non-opioid treatments, and insist on naltrexone. Many people insist specifically on Vivitrol, the long-lasting naltrexone injection.
For women who are already on Vivitrol and then discover that they are pregnant, they will want to know if it is safe to continue Vivitrol. If they are still in early recovery, in the first few months, it may be best to continue with Vivitrol treatment.
The risk of relapse is high if medical treatment is discontinued too soon. And, it would not make sense to switch a patient on Vivitrol to Suboxone, and they most likely would refuse that therapeutic change.
Of course, a woman on Vivitrol would have the option to stop taking the naltrexone shot at any time. There is no issue with opioid withdrawal symptoms when quitting Vivitrol.
However, the major risk would be the possibility of the patient developing opioid cravings and possibly relapsing on opioids during pregnancy. Because of this risk, the patient should have a serious talk with their Vivitrol doctor about continuing treatment throughout their pregnancy.
Further research on naltrexone in pregnancy must be performed.
It is important to learn more about the effects of naltrexone in pregnancy. While animal studies are interesting, we need to know more about the safety of the drug in human pregnant women.
Women who choose to continue Vivitrol during pregnancy may provide an opportunity to learn more. Doctors could possibly study the effects that may occur, regarding human fetuses.
Pregnancy always presents a challenge in researching medication effects because, in most cases, drugs cannot be studied during pregnancy. For obvious reasons, it would be wrong to perform pharmaceutical studies on pregnant women.
Because of this reason, we do not have as much information as we would like on the safety of various drugs in pregnancy. Yet, when it comes to addiction treatment, the risk of not providing medical treatment is so great, that doctors and patients choose to take the smaller risk of medical treatment to provide the best protection for both mother and baby.