Opioids Half life of MScontin

[paranoid android]

I know the half life of morphine is about 4 hours but since mscontin is time release wouldnt the half life be longer? Any help would be appreciated

 

[Deleted member 554582]

12 hours i think....the doses are usually two at a day...on very 12 hours...just like oxycontine....in fact for many is lower

 

[paranoid android]

12 hours i think....the doses are usually two at a day...on very 12 hours...just like oxycontine....in fact for many is lower

The pills are sustained release so i guess it would be 12 hours plus the half life of morphine? Thats a total of 16 hours

 

[PenguinWithNapalm]

I know the half life of morphine is about 4 hours but since mscontin is time release wouldnt the half life be longer? Any help would be appreciated

From what I could find on the internet it says that the terminal half life is around 15 hours depending on renal and hepatic function.

 

[paranoid android]

From what I could find on the internet it says that the terminal half life is around 15 hours depending on renal and hepatic function.

Im just wonderng because i have a drug test tomorrow. Im suppsed to be on MScontin but only 30mg's a day. So ikm going to not take any extra morphine for 24 hours just ihn case

 

[PenguinWithNapalm]

Im just wonderng because i have a drug test tomorrow. Im suppsed to be on MScontin but only 30mg's a day. So ikm going to not take any extra morphine for 24 hours just ihn case

Oh okay. So are you worried they are going to test your levels?

 

[paranoid android]

Oh okay. So are you worried they are going to test your levels?

Ya thats why for 24 hours im going to take my prescribed dose

 

[PenguinWithNapalm]

Ya thats why for 24 hours im going to take my prescribed dose

Do you know for a fact that they are going to test your levels or are you just worried about it?

 

[paranoid android]

Do you know for a fact that they are going to test your levels or are you just worried about it?

Just worried about it

 

[PenguinWithNapalm]

Just worried about it

Oh okay. Yeah it looks like they do indeed test levels. I wish you the best my friend. I feel like 24 hours might be enough to level it out since 1-4 days is for it to get out completely. Everyone’s body is different so I can’t imagine they are super strict

 

[paranoid android]

Oh okay. Yeah it looks like they do indeed test levels. I wish you the best my friend. I feel like 24 hours might be enough to level it out since 1-4 days is for it to get out completely. Everyone’s body is different so I can’t imagine they are super strict

I think im gonna wait till later to do the test

 

[TheFunkeeJunkee]

To calculate the apparent half life (what pharmacologists call the half life of extended release drugs) of a drug formulated with a constant-rate extended release mechanism you can use the following formula:

Effective half life = biological half life + extended release duration / 2

So for MSContin we can do this:

Effective half life = 4 hours + (12 hours / 2) = 10 hours

It's important to mention that this is only the case with constant-rate preparations and not other ER mechanisms, like combination release (Concerta or Adderal XR).

 

[paranoid android]

To calculate the apparent half life (what pharmacologists call the half life of extended release drugs) of a drug formulated with a constant-rate extended release mechanism you can use the following formula:

Effective half life = biological half life + extended release duration / 2

So for MSContin we can do this:

Effective half life = 4 hours + (12 hours / 2) = 10 hours

It's important to mention that this is only the case with constant-rate preparations and not other ER mechanisms, like combination release (Concerta or Adderal XR).

Thanks

 

[paranoid android]

To calculate the apparent half life (what pharmacologists call the half life of extended release drugs) of a drug formulated with a constant-rate extended release mechanism you can use the following formula:

Effective half life = biological half life + extended release duration / 2

So for MSContin we can do this:

Effective half life = 4 hours + (12 hours / 2) = 10 hours

It's important to mention that this is only the case with constant-rate preparations and not other ER mechanisms, like combination release (Concerta or Adderal XR).

Wait how can it have a 10 hour half life if its a 12 hour release pill? Or am i reading this completely wrong

 

[TheFunkeeJunkee]

Wait how can it have a 10 hour half life if its a 12 hour release pill? Or am i reading this completely wrong

MSContin releases morphine over 12 hours it is simultaneously being metabolised and eliminated. Because of this plasma concentration begins to decline before the 12 hours of release is complete.

This concept can be a bit tricky to understand but don't confuse formulation duration (the amount of time it takes for the tablet to release its contents) and terminal half life (the amount of time it takes for plasma concentration to half).

 

[ty8705]

MSContin releases morphine over 12 hours it is simultaneously being metabolised and eliminated. Because of this plasma concentration begins to decline before the 12 hours of release is complete.

This concept can be a bit tricky to understand but don't confuse formulation duration (the amount of time it takes for the tablet to release its contents) and terminal half life (the amount of time it takes for plasma concentration to half).

Exactly. Everyone responds different. For me, OxyContin 20 gives me relief for about 4-5 hours. I start to feel withdrawals around hour 10-11. It’s been like that for me since my first dose a few years back.

 

[4DQSAR]

I think @ty8705 makes the important point that everyone is different so while we may known the mean values, a lot of things can influence any simple calculation.

Regardless of formulation, liver enzymes and non-specific blood enzymes all influence the plasma levels of morphine.

Now a proper analysis would test for morphine, N-desmethylmorphine and probably morphine-3-gluconate to estimate total dose. But I suspect such specific analysis would not typically be undertaken. That would reach back to test if dosing was acute or chronic so likely only used if a COD needs to be established.

 

[PtahTek]

just anecdotal but i feel free of pains/aches til the next day from a 10 or 20mg.
damn i wanna