User145667
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If I got Prolonged QT interval symptoms from mixing Lexapro and Suboxone, is it likely that the same will happen if I mix Methadone with Lexapro?
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BDD Moderators: Keif’ Richards | negrogesic
Opioids Question about Methadone and Lexapro
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AlsoTapered
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Lexapro is escitalopram is it not? Well, while the racemic drug, citalopram has been demonstrated to produce long-QT at therapeutic doses escitalopram does not (although supratherapeutic dose AKA overdoses) it has been demonstrated that it can. Methadone can also produce long-QT in certain individuals, but it appears to be levomethadone that is responsible. So levomethadone has no advantages.
Buprenorphine has also been shown to produce long-QT.
but the key to all this is that the effects are dose related, Simply put, the more you take, the more likely long-QT will result.
So the question is, why is levomethadone used? I believe it's given for pain in certain nations. I conclude that the use of levomethadone reduces those pharmacokinetic inconsistencies that methadone is known for. Specifically the time to peak plasma concentrations (2.5-5.5 hours), T½ (17-25 hours) and oral bioavailability (49-78%). The values for levomethadone seem vastly more uniform between patients.
A historical note - Methadone was first trialled in 1942 and was only administered parenterally (IV is the only named route). Obviously this immediately solves the time to and absolute peak-plasma levels. It was also administered twice a day, But it wasn't widely adopted as it was considered too toxic (by 1942 standards!).
It STILL demonstrated a wide range of T½ and just to make things even more complex. that T½ value decreases upon chronic administration!
Put simply - if methadone was discovered today, it would not receive a marketing licence while levomethadone likely would.
If you can tolerate buprenorphine, it's a more modern drug and is more widely used for it's analgesic properties. But take note of the fact that the discoverers of buprenorphine specifically state that it was intended for opioid detoxification. It was never intended to be used for months or years,
If you truly wish to stop, a few days to stabilize and then a few weeks of reduction to NO opioids seems effective. People who have been on it for years, being 'parked' on buprenorphine appears to produce exactly the same results as patients parked on methadone i.e. you never get clean.
Sorry for the long post but I spent a long time researching methadone and it's analogues. It's history is rich but at the end of the day, I'm sure it's the low price that makes it so successful because it has almost no other positive attributes.
I admit - I WAS surprised to discover that levomethadone is almost entirely responsible for QT elongation. Like most people I assumed it was safer.
Buprenorphine has also been shown to produce long-QT.
but the key to all this is that the effects are dose related, Simply put, the more you take, the more likely long-QT will result.
So the question is, why is levomethadone used? I believe it's given for pain in certain nations. I conclude that the use of levomethadone reduces those pharmacokinetic inconsistencies that methadone is known for. Specifically the time to peak plasma concentrations (2.5-5.5 hours), T½ (17-25 hours) and oral bioavailability (49-78%). The values for levomethadone seem vastly more uniform between patients.
A historical note - Methadone was first trialled in 1942 and was only administered parenterally (IV is the only named route). Obviously this immediately solves the time to and absolute peak-plasma levels. It was also administered twice a day, But it wasn't widely adopted as it was considered too toxic (by 1942 standards!).
It STILL demonstrated a wide range of T½ and just to make things even more complex. that T½ value decreases upon chronic administration!
Put simply - if methadone was discovered today, it would not receive a marketing licence while levomethadone likely would.
If you can tolerate buprenorphine, it's a more modern drug and is more widely used for it's analgesic properties. But take note of the fact that the discoverers of buprenorphine specifically state that it was intended for opioid detoxification. It was never intended to be used for months or years,
If you truly wish to stop, a few days to stabilize and then a few weeks of reduction to NO opioids seems effective. People who have been on it for years, being 'parked' on buprenorphine appears to produce exactly the same results as patients parked on methadone i.e. you never get clean.
Sorry for the long post but I spent a long time researching methadone and it's analogues. It's history is rich but at the end of the day, I'm sure it's the low price that makes it so successful because it has almost no other positive attributes.
I admit - I WAS surprised to discover that levomethadone is almost entirely responsible for QT elongation. Like most people I assumed it was safer.
4meSM
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Are you sure about that?
Every reference I've come across states that dextromethadone is several times more effective at blocking hERG potassium channels than levomethadone...
AlsoTapered
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I was just as surprised as you.
4meSM
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"LevoMTD's weaker ability to interact with hERG channels and, as a result, its weaker association with QTc prolongation and TdP, have been confirmed by the observation that 90% of patients receiving MTD treatment with a QTc prolongation underwent a normalization of the QT value (<470ms in men and <480ms in women) after switching from MTD to levoMTD."
AlsoTapered
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