Heroin Methadone and Heroin

[opiandy]

I've been on methadone for a few years and have tapered down from 120mg to 20mg daily. I stopped for about a week when I used some oxycodone for a few days, then used some heroin. My tolerance for heroin was low since I hadn't used in several years, so I felt the effects easily.

That lasted a few days and now I have been back on methadone for about a week now at 20mg/day. The last dose of methadone was at 11:00 pm last night. Would the methadone block the effects of any heroin I did right now? How long does it block the effects if I have been dosing daily for a week?

 

[MedicinalUser247]

As far as I know I've never heard of Methadone blocking the effects of any Opiate. You must be thinking of something else. Methadone would increase the effects of Heroin. Don't take them together because you'll most likely O.D. Just try staying on your Methadone and keep away from Heroin.

 

[opiandy]

Methadone's clinical purpose is to bind to the mu-opioid receptors, blocking other opiates by not allowing them to bind to the receptors.

 

[MedicinalUser247]

Does anyone know more about Methadone ? Opiates aren't my category.

 

[Psycho_Logic]

As far as I know I've never heard of Methadone blocking the effects of any Opiate. You must be thinking of something else.

Well there were some people who understand pharmacology better than myself and they claimed that above 60-80mg methadone starts blocking other opioids.

I allways thought thst methadones "blocking effects" is actually increased tollerance. So in the era of true heroin a good dose of H is bot felt because 100mg of chronic methadone (actually much more as methadone accumulates due to long effects/half life) cruising through your blood increased tolerance so much that H becomes not strong enough.

Unfortunately there was a common practice off "breaking through methadone". People symply increased their dose in the shot to ridiculous amounts. Plus 20-25 years ago H was very pure im my country due to the raging war. It was also everywhere...

Back to the subject. There were cases when they broke through successfully and were unmistakably hihg on H. There were cases of wasted shot. And there were many cases of fatal OD. Many people I knew died trying to break through 100mg or more of methadone. Other big threat was speedball.

But if methadone is an opioid blocker how in the world people were able to successfully break through 120mg of daily methadone? If you get someone accustomed to 3G of oxycodone would oxycodone becone a blocker. If the name of the game is tolerate increaae I do not consider that a blocking agent like buprenorphine.

But I am no scientist so I don't know all of merhadons modes of action. All I have is the experience and giving people 100+ mg of methadone prety hastily.

Besides 20mg will not block good quality heroin. It will boost the severity of the overall opioid intake and increase the OD risk substantially.


Proceed with caution.

 

[martincertain]

Methadone isn't a blocker but does have a high binding affinity (as a full agonist). In my experience, I find it harder to get high from H if I've taken Methadone, but if the dope is good then you should still feel it on 20mg. It won't block any heroin, it will just decrease the potential binding affinity to mu receptors.

Buprenorohine/Subuxone is a full blocker (maybe where you're getting mixed up).

 

[Psycho_Logic]

Methadone's clinical purpose is to bind to the mu-opioid receptors, blocking other opiates by not allowing them to bind to the receptors.

Ranking opioids solely based on their binding affinity to mu-opioid receptors can be challenging due to variability in available data. However, based on the general consensus in the literature, here's a list of commonly used opioids ranked by their binding affinity to the mu-opioid receptor from strongest to weakest:

1. **Carfentanil** (highest binding affinity)
2. **Sufentanil**
3. **Fentanyl**
4. **Alfentanil**
5. **Remifentanil**
6. **Buprenorphine** (very high affinity but partial agonist)
7. **Oxymorphone**
8. **Hydromorphone**
9. **Methadone**
10. **Levorphanol**
11. **Heroin** (diacetylmorphine, metabolized to 6-MAM and morphine)
12. **Oxycodone**
13. **Morphine**
14. **Hydrocodone**
15. **Codeine**
16. **Meperidine (Pethidine)**
17. **Tapentadol**
18. **Tramadol** (low affinity, also works on serotonin and norepinephrine reuptake)
19. **Pentazocine** (mixed agonist-antagonist)
20. **Butorphanol** (mixed agonist-antagonist)

This ranking is based on binding affinities derived from in vitro studies and receptor binding assays. Actual clinical potency can differ due to other pharmacokinetic and pharmacodynamic factors.

So oxymorphone and hydromorphone are stronger mu opioid receptor blockers than methadone is. Now it makes sense why "back then" hydromorphone (in the 24 hours SR formulation , brand name Jurnista) was used over here for ORT. It is a high potency opioid with binding affinity higher than methadone.

 

[Lv1985]

Definitely blocked heroin for me, but I was smoking it. That was actually the best part, once I got on methadone I kept smoking for about a month. Once my dose was at 45-50mg I could smoke $100 of good tar and feel nothing. Broke my mental association with heroin and feeling good which made things easier.

 

[joesmyname]

Methadone isn't a blocker but does have a high binding affinity (as a full agonist). In my experience, I find it harder to get high from H if I've taken Methadone, but if the dope is good then you should still feel it on 20mg. It won't block any heroin, it will just decrease the potential binding affinity to mu receptors.

Buprenorohine/Subuxone is a full blocker (maybe where you're getting mixed up).

this.

 

[Keif' Richards]

Methadone is not an Opioid antagonist at any dosage. The concept of a "blocking dose" can make things confusing for people. As stated, there is not a dose at which Metha done changes from an agonist to an antagonist. What is being described is the phenomenon of Opioids in general. becoming less pleasurable as the dose is increased. Basically, a person might still want to do Heroin even if they're maintained on a high dose of Methadone. What happens is that the cost/benefit ratio decreases and there is less of a reason for a person to decide to spend money, buy Heroin and be underwhelmed by the experience. For a lot of people, this transition happens at around 80mg-120mg.

Methadone does not function differently than your other garden variety Opioid agonists in this way. Yes, it also functions as an N-Methyl-D-Aspartate NMDA antagonist, which is not especially common, but that really is not relevant to what we're describing here.

Methadone is not going to block you feeling the effects of the Heroin.

 

[Psycho_Logic]

Exactly @Keif' Richards ! Even oxy or hydromorphone have higher mu-opioid receptor binding affinity and would displace methadone from the mu-opioid receptor, not to mention fentanyl. This was main reasons why 24h slow release hydromorphone was taken off the list of opioid replacement therapy in my country 20 years ago - people just blasted through high doses of methadone and it became more sought than heroin on the streets by people that were forced to ORT (other option was jail time). Heck, even heroin that has lower affinity in high enough doses was good enough to blast through 80-120mg of methadone. Unfortunately as methadone is not a blocker this technique caused many fatal ODs. Here is the list once again:

However, based on the general consensus in the literature, here's a list of commonly used opioids ranked by their binding affinity to the mu-opioid receptor from strongest to weakest:

1. Carfentanil(highest binding affinity)
2. Sufentanil
3. Fentanyl
4. Alfentanil
5. Remifentanil
6. Buprenorphine (very high affinity but partial agonist)
7. Oxymorphone
8. Hydromorphone
9. Methadone
10. Levorphanol
11. Heroin (diacetylmorphine, metabolized to 6-MAM and morphine)
12. Oxycodone
13. Morphine
14. Hydrocodone
15. Codeine
16. Meperidine (Pethidine)
17. Tapentadol
18. Tramadol (low affinity, also works on serotonin and norepinephrine reuptake)
19. Pentazocine(mixed agonist-antagonist)
20. Butorphanol
(mixed agonist-antagonist)

Methadone is full agonist opioid that is given in high doses to push tolerance up so user can't safely take heroin cause fatal OD in that case is very real possibility. Plus how will you feed that kind of habbit when your tolerance is thrughh the roof? I thought that this was settled long time ago...