Methadone vs. Suboxone: What’s the Difference?

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Sarz Maxwell, MD Psychiatrist

What’s the difference between Methadone and Suboxone? I’ll try to make this short and simple. Throughout, ‘Methadone’ means any form of Methadone given by licensed Narcotic Treatment Programs (NTP), and ‘Buprenorphine’ means Suboxone or Subutex—any sublingual (under-the-tongue) pill or film. There are individual preferences, but basically all forms of the two medications are the same.

Each has advantages and disadvantages, but both work well to treat opiate addiction. As a physician, I believe Methadone and Buprenorphine classify as wonder drugs: they work for the majority of people without dangerous or disabling side effects. Very few medications can say that.

Methadone was first used in this country in the 1960’s to treat heroin addicts, by Drs. Nyswander and Dole in New York. They concluded the average dose should be 80-140mg/day—some people need less, some need more. Today, with people addicted to high-potency prescription opiates, average doses probably need to be higher.

Methadone can only be prescribed by Narcotic Treatment Programs, and only under restrictive federal guidelines. A physician may prescribe Methadone (or other opiates) for pain, but it is a felony to prescribe Methadone for opiate addiction. We get into a very slippery slope here, as many opiate addicts also have chronic pain, and DEA can get very sticky about prescribing for them. Doctors can and do lose their licenses simply because they do the compassionate thing, so docs are very careful about prescribing Methadone.

  • Methadone is a pure opiate agonist: it binds to the opiate receptor and turns it ‘on’.
  • Naloxone is a pure opiate antagonist, which binds to the opiate receptor and switches it ‘off’, blocking the effect of agonists. A pure agonist can cause overdose, and death.

Antagonists reverse overdose and prevent death.

Following me so far? It gets worse.

Buprenorphine is a mixed agonist/antagonist. It binds to the opiate receptor and switches it either ‘on’ or ‘off’ according to how many receptors are occupied—receptors with an opiate (including Buprenorphine itself) bound to them. If the number of receptors occupied is low, Buprenorphine turns the receptor ‘on’. If the receptors occupied is high (especially with pure agonists), Buprenorphine turns the receptor ‘off’ and causes withdrawal (so it’s very safe against overdose). This means when you start Buprenorphine there must be no opiates in your system, or the Buprenorphine will cause severe withdrawal. This makes it very hard to switch from Methadone to Buprenorphine, because Methadone stays in your system long after the last dose. Switching from Buprenorphine to Methadone, however, is simple.

127263Besides agonist/antagonist, you must also understand receptor affinity. A drug molecule with greater receptor affinity will displace (kick out) other molecules and occupy the receptor.

In general, receptor affinities go like so:

Heroin ( Oxycodone | Hydrocodone)

Methadone | Naloxone | Buprenorphine

Methadone will displace and preferentially occupy the receptors over heroin, etc., so when you’re taking Methadone, using heroin, etc. doesn’t get you (as) high. Naloxone will displace all agonists—it will reverse an overdose and keep you from dying. Buprenorphine has the highest receptor affinity.

The Suboxone pill contains two drugs: buprenorphine and naloxone. Theoretically, if Suboxone is crushed and injected, the Naloxone will cause withdrawal. However, Buprenorphine has higher receptor affinity than Naloxone, so Naloxone can’t bind to the receptors. Injecting Buprenorphine often does cause withdrawal, though, because people inject it while there’s still agonist in the receptors, so Buprenorphine displaces them and turns the receptors ‘off’, causing withdrawal. The Naloxone in Suboxone has no effect. Think of it as food coloring.

Buprenorphine’s biggest advantage is it’s available as a prescription from certain doctors with special license: you simply get a prescription and fill it at the pharmacy. If you travel, you carry a single bottle with a pharmacy label rather than a bunch of bottles with a Methadone clinic label (or guest-dosing at another clinic). Your Buprenorphine doctor will have rules, like coming to the office regularly, or going to groups or counseling, but it’s not as restrictive as the rules governing methadone clinics.

Buprenorphine’s biggest disadvantage is price. Many insurances pay for it, but most (like Public Aid) only cover for a year. Buprenorphine, even generic, costs $300-$1200/month.

Methadone’s biggest advantage is being a full agonist, making it stronger, and best for pain management. Buprenorphine helps with mild pain, but Methadone is far superior. Methadone treatment is fairly inexpensive: most clinics cost ~$100/week, including medication, individual and group counseling, and doctor visits as necessary—not a bad deal.

Both medications are totally safe in pregnancy

Buprenorphine may cause less neonatal withdrawal, but the withdrawal is easily managed (breastfeeding) helps. The medications are totally benign, but withdrawal can be deadly to the fetus, so a woman should never taper off Methadone or Buprenorphine while she’s pregnant. Methadone is still the gold standard for a pregnant woman, because it’s been around so long: millions of women on Methadone have delivered strong, healthy babies who grew up normally.

Bottom line: both Methadone and Buprenorphine are excellent treatments for opiate addiction. Both are safe for long-term use, and safe in pregnancy. Methadone is cheaper, and works better for pain management. — Sarz Maxwell, MD Psychiatrist Galena Clinic

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