Switching to pregabalin or gabapentin from methadone

[Cedarish]

I have very much appreciated the information here over several years but never posted before.

I have been able to control my RLS (which I’ve had since teen years along with several family members - I’m now 80) with a divided 10 mg daily dose of methadone, prescribed by my sympathetic GP here in Canada. Previously I was on gabapentin with good benefit for quite a while but it stopped working several years ago. I tried suboxone briefly but didn’t find it that much superior to the methadone, and it was more expensive.

My problem right now is that I believe methadone has suppressed my appetite, to the point I am now quite underweight, and also have mild to moderate but persistent depression and sometimes mild nausea.

My question is whether anyone has experienced withdrawing from methadone (or other opioid) and successfully resumed gabapentin or pregabalin? I’m hoping I could do that and one of the latter meds would have become effective again after such a long ‘holiday.’ I am very fearful of stopping the methadone since it allows me to sleep, but I don’t like the side effects and also don’t like being dependent on an opioid. Many thanks for any advice.

[SueJohnson]

Yes you can withdraw from methadone but you need to do it very slowly under the supervision of your doctor.

You say the gabapentin stopped working. How much were you taking? Did you take it in divided doses?

[SueJohnson]

Have you had your ferritin checked? If so, what was it? This is the first thing your doctor should have done. Improving your ferritin to 100 or more helps 60% of people with RLS and in some cases completely eliminates their symptoms. If not when you see your doctor ask for a full iron panel. Stop taking any iron supplements including in a multivitamin 48 hours before the test, avoid a heavy meat meal the night before and fast after midnight and have your test in the morning before 9 am if possible. When you get the results, ask for your ferritin and transferrin saturation (TSAT) numbers. You want your transferrin saturation to be over 20% but less than 45% and your ferritin to be at least 100. If they are not, post them here and we can give you some advice.

[Cedarish in reply to SueJohnson]

Thanks very much, Sue, for this info and for your speedy reply. I cannot remember the gabapentin dosage now, but I think it was never very high compared to some levels I’ve seen mentioned here, and I’m pretty sure I didn’t take it in divided doses. That is one of the valuable things your posts have taught me. Would you recommend pregabalin or gabapentin? I believe Horizant is not available in Canada.

As for the iron panel, it is a few years since I’ve had one but my doctor did request it more than once in the past and assured me my levels were OK. However, I am seeing him again this coming week and will ask for it to be done again - no doubt things can change - and compare the results with your recommendations.

[SueJohnson in reply to Cedarish]

Then gabapentin or pregabalin may very well work for you. I usually recommend one start out with gabapentin because you can increase it in smaller amounts and then once you find out the amount that works for you you can switch over to pregabalin if you want by dividing the gabapentin dose by 6.

Horizant is available in Canada but is expensive and very few people need it since RLS is generally only at night. Horizant lasts 24 hours and is taken once a day although some don't find it lasts that long.

Doctors will say your ferritin is fine when what is fine for others isn't fine for those of us with RLS.

You have probably seen this but in case you haven't: Beginning dose is usually 300 mg gabapentin (75 mg pregabalin) [If you are over 65 and susceptible to falls beginning dose is 100 mg (50 mg pregabalin).] It will take 3 weeks before it is fully effective. After that increase it by 100 mg (25 mg pregabalin) every couple of days until you find the dose that works for you.

Take it 1 to 2 hours before bedtime as the peak plasma level is 2 hours. If you need more than 600 mg take the extra 4 hours before bedtime as it is not as well absorbed above 600 mg. If you need more than 1200 mg, take the extra 6 hours before bedtime. (You don't need to split the doses with pregabalin)

Most of the side effects will disappear after a few weeks and the few that don't will usually lessen. Those that remain are usually worth it for the elimination of the RLS symptoms. According to the Mayo Clinic Updated Algorithm on RLS: "Most RLS patients require 1200 to 1800 mg of gabapentin (200 to 300 mg pregabalin)."

If you take magnesium even in a multivitamin, don't take it within 3 hours of taking gabapentin (it is OK with pregabalin) as it will interfere with the absorption of gabapentin and don't take calcium within 2 hours for the same reason (not sure about pregabalin). Check out the Mayo Clinic Updated Algorithm on RLS which will tell you everything you want to know including about its treatment at Https://mayoclinicproceedings.org/a...

[Cedarish in reply to SueJohnson]

Thanks for some more essential details, Sue. These are the additions which can make or break success with medication changes, I think. I will report back how things go.

[Merster]

Cedar ish I posted earlier about my suc es with slow release Morphine along with ropinerole. Last year I tried methadone and suboxone for 6 months and couls not tolerate either. I went back to the Ms contin and requip and have been fine w er since.. toughest part is finding a doctor who cares enough to trust you with an opioide