All you can do is lower your dose and then go up again. When you're on really low doses, you only need really low increases to feel a lot more high. When you're on a really high tolerance,you need a LOT more to feel anything. You're on a pretty high dose. I'm a pretty heavy heroin user but that's still more methadone than I need to feel buzzed from it. Not enormously more, but definitely notably more. No there isn't a ceiling dose. Not in the conventional sense of the word. But it is a dose where only a BIG jump in methadone is probably gonna be enough for you to really feel it. And you don't wanna do that. It's just making things harder later on.
People wind up on absurd doses of methadone this way, and wind up only being able to get high properly on methadone. And think of the methadone withdrawal on that kinda methadone dose. Not fun. Sorry man, but the poster above me is right. This is why they use methadone. For this exact purpose. You can't get high, you probably can't affordably switch to something else without feeling sick too. And you can't lower your tolerance quickly without feeling sick. If you still want to get high, you pretty much just gotta use methadone for those times when you can't get any of your DoC. Or to taper down on your own. My recollection is a lot of clinics in the US kick you off if you use on top of methadone. Fortunately down here in NSW, Australia, mine at least, follows a harm reduction model and I know people who've never passed a drug test in 3 years going there and and still get their methadone. I've been going nearly a year and my tests come back dirty for heroin, meth, cannabis, benzodiazapines, etc. Sometimes even all at once. And they still just give me my methadone so I don't get sick. I actually am getting sick of this life and am truly thinking of getting off heroin and taking recovery seriously now, but it was a great option so I wouldn't get sick back when I wasn't. Unfortunately it's not like that everywhere.
Methadone will stop you getting high from any other opiate either once you're at a high enough dosage. Which you may well have already surpassed. The highest ive been on so far is 95mg. On that I still felt heroin, but I was using a lot of it before and after getting on the methadone. I probably never reached a blocking dosage. You're on quite a bit more than me though and it sounds like you're tolerant to it. They generally won't let you increase your dosage fast enough for it to give you any satisfaction from it.
If you were going to my clinic, you could just stop going for a little while and the idiots there eventually assume they have to halve your methadone dose or start you all the way down at 30mg again, or you'll overdose cause in their mind your tolerance can completely disappear or be halved in only 3-4 days. Regardless of if you've been using heroin in the meantime. Which was fine when it happened to me (I didn't do it on purpose I just couldn't get there on time for nearly a week) because I could get enough heroin to make up the difference.
Also you gotta remember, they make you take it orally (and I highly recommend that be the only way you take this particular drug, which I say being a multiple times a day IV heroin user), so you don't get it into your system that fast anyway.
Methadone and buprenorphine have been chosen in particular because the goal of the people making he choice is to get you off drugs, and help you stop using opiates without the pain of withdrawal, but to not let you easily get high from them, or while on them if they can help it. Bup is even worse in this particular regard because it actually chemically prevents other opioids from attaching to, or remaining attached to their cellular receptors. Methadone on the other hand just saturates the receptors preventing your DoC from working very well once the methadone is above a certain dose. At least unlike buprenorphine using on methadone isn't infeasible or running the risk of precipitated withdrawal.
I suggest you think about why you're on methadone. What it is you want at this point in your life. And hey, I'm not you, maybe getting off drugs, not getting high anymore, just isn't what you want yet, maybe you're not ready for that in your life yet. If that's the case then neither I nor anyone else here has the right to judge you for that decision. We're ready when we're ready, nobody else's timetable matters. On the other hand if you've been thinking of stopping for a while, this may be a sign that it's time to start living life without getting high every day. Again I don't know, I still do get high and shoot up every day. I'm high now. I hope to stop one day very soon, I got removed from methadone because my car broke down, and I'm still using to ward off withdrawal, but the cars fixed now and I'm trying to go back and soon as I do I intend on stopping my recreational opiate use for the indefinite future. Maybe ill succeed maybe I won't. Perhaps you should ask yourself questions like these if you're not sure what you want. But if you do know what you want, and what you want is to keep getting high. Likely your only option is to drastically lower your methadone dose, and then either start going back up again or using your DoC again.
I wish you luck man, whatever you want, whatever you decide. It's you're life. Take care.
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