PDA

View Full Version : Any Doctors or Nurses in the house?? (Drug interaction questions)



EFCollins
02-26-2011, 07:02 AM
I am researching for a novel. My MC is an undiagnosed schizophrenic and also a heroin addict. He's receiving treatment for both of these things at different times, at different places.

MC goes to the hospital for an overdose on heroin. He is held for x amount of days, psych eval because the delusions, hallucinations (audible and visual) continue even after he is given adrenaline and time to come down from his high. The doctors prescribe risperidone.

Not long after, he gets in trouble and has to return to the drug court (fails the drug test, obviously) but with the extent of his problems, he is sent to an intensive rehab. There, my main character does not share that he is on risperidone, and methadone is administered at a high dosage. He nearly dies... syncope, heart palpitations, and other effects of mixing the two drugs.

There are some things in the articles I'm reading about this in my research that I don't understand and reading other articles on what I'm not getting is only causing further confusion.

Methadone and risperidone have an effect on the QT intervals and risperidone does something to the metabolism of methadone? What? I haven't got a clue what this means and searching up QT intervals and methadone metabolism is just confusing me further.

Basically, what are QT intervals and how does mixing these two drugs effect it? I understand that it is prolonged... but what does that mean in terms of how it effects the body?

What does the article mean when it says that risperidone can "inhibit the metabolism of methadone"?

Any other information any of you feels up to offering, I'll be happy to listen... I've been on the NIMH site, drugs(dot)com, and a few other sites that have articles on schizophrenia, risperidone, methadone, heroin addiction, interaction articles with methadone and risperidone as the focus... But I'm starting to get really confused. The medical terminology is getting to be a bit much. I have no idea what QT intervals are. And reading further about them, I get lost in the jargon.

Help? And thank you to anyone willing to give it.

Drachen Jager
02-26-2011, 07:38 AM
http://en.wikipedia.org/wiki/QT_interval

It would help if you could point to the articles, methadone does not have a "metabolism", are you thinking it interferes with the body's ability to metabolize methadone?

I am not an expert but if I could read the articles I'm sure I could help clarify things.

EFCollins
02-26-2011, 07:54 AM
No. The bit I quoted above (in quotation marks, I mean) was a copy/paste directly from the website.

Hang on... let me go back through my history and get the articles. I've already closed the tabs so give me a few minutes.

EFCollins
02-26-2011, 08:05 AM
http://www.drugs.com/drug-interactions/methadone-with-risperidone-1578-0-2019-0.html

(The above article is the one that talks about the Metabolism of Methadone)

http://www.ehealthme.com/drug_interactions_side_effects/Clozaril-2661325

http://www.nimh.nih.gov/health/publications/schizophrenia/index.shtml

(The above link is to the contents page of the articles I read... and I read them all)

http://www.nlm.nih.gov/medlineplus/druginfo/meds/a694015.html


No offense, but I never go to Wikipedia for medical information. Anyone can write on Wiki. I could go right now and change that article to reflect anything about the QT interval that I want to. I'll stick with medical sites that are run by pharmaceutical companies, doctors and other medical professionals. Wiki is just too easy to cite and change... even if you're a third grader with no business doing it.

http://www.herbs2000.com/medica/risperidone.htm

First site I went to... which is what led me to the interaction in the first place. Now, I'll go find the articles I read about QT and metabolism so you can see why I was confused. Check this post for changes.

QT Interval:

http://www.ecglibrary.com/l_qt.html

http://www.cvphysiology.com/Arrhythmias/A009.htm (scroll to the bottom where the QT interval section is)

http://heartdisease.about.com/od/palpitationsarrhythmias/a/QT_drugs.htm

Metabolism of Methadone:

http://onlinelibrary.wiley.com/doi/10.1002/chir.10303/abstract

http://www.atforum.com/SiteRoot/pages/addiction_resources/Drug_Interactions.pdf (note that this is a PDF document, so you need a pdf reader to view it. I recommend Foxit)

http://www.ncbi.nlm.nih.gov/pubmed/14628297

Yeah. Over my head? Yup.

EFCollins
02-26-2011, 08:15 AM
Updated links above.

Drachen Jager
02-26-2011, 10:16 AM
Ahh, okay, I was unaware the 'metabolism' could be used in that context.

It just means that the rate at which the body processes the methadone, I am unclear whether they are referring to how quickly the methadone takes effect or how quickly the body purges methadone, but I am fairly sure it is the latter. That would mean the methadone stays in the system much longer.

Prolonging the QT interval creates a risk of arrhythmia which can lead to cardiac arrest.

I am no expert, I am just good at internet research. I hope that was some help.

The wikipedia article on QT interval was helpful to me. http://en.wikipedia.org/wiki/QT_interval

waylander
02-26-2011, 12:32 PM
It just means that the rate at which the body processes the methadone, I am unclear whether they are referring to how quickly the methadone takes effect or how quickly the body purges methadone, but I am fairly sure it is the latter. That would mean the methadone stays in the system much longer.

Prolonging the QT interval creates a risk of arrhythmia which can lead to cardiac arrest.


DJ is correct
This could lead to accumulation of methadone in the body.

PinkAmy
02-26-2011, 02:56 PM
Off topic question, how is your MC getting methadone in intensive drug treatment? There's no way he got away with bringing to rehab (I've heard of people trying to smuggle drugs in their butts and getting caught during intake because some places do cavity checks). Plus on strong psychotropics, he would be monitored and not given long term prescriptions. They usually do blood tests every 3 months for risperodone pts to monitor for liver damage (I interned in a state hospital with schizophrenics coming out the wazoo).
I'm also not sure he'd be given risperodone right away, because sometimes schizophrenics use drugs to self medicate against their symptoms and sometimes their symptoms come from drug use and not a psychotic disorder. Of course, dual diagnoses are also not uncommon, but psychiatrists would closely monitor the pt (if the patient complies once out of the hospital) during the beginning to be sure about dosage and side effects. He's probably see a psychiatrist weekly in the beginning (just for a 10-15 minute med check). I have no idea if there is a black market for risp. --if he stopped seeing the psychiatrist he could probably find it on the street or internet. I wouldn't want to be your mc, LOL.

boron
02-26-2011, 03:04 PM
Risperidone can slow down the degradation (aka "inhibit the metabolism") of methadone, which would therefore have a prolonged and stronger effect.

One of the effects of methadone alone or risperidone alone (and especially both together) is a prolonged QT interval (as seen on the ECG), which denotes the phase of the heart beat from the beginning of the electric excitement of the heart ventricles to the end of their excitation. A prolonged QT interval as such does not cause any symptoms or anything, but it shows there is a risk for a heart arrhythmia to develop; in the case of methadone and risperidone combination, this could be a specific form of tachycardia (fast heart beat) called "torsades de pointes ventricular tachycardia", which has a typical and easily recognizable ECG pattern.

.

EFCollins
02-26-2011, 07:35 PM
Off topic question, how is your MC getting methadone in intensive drug treatment? There's no way he got away with bringing to rehab (I've heard of people trying to smuggle drugs in their butts and getting caught during intake because some places do cavity checks). Plus on strong psychotropics, he would be monitored and not given long term prescriptions. They usually do blood tests every 3 months for risperodone pts to monitor for liver damage (I interned in a state hospital with schizophrenics coming out the wazoo).
I'm also not sure he'd be given risperodone right away, because sometimes schizophrenics use drugs to self medicate against their symptoms and sometimes their symptoms come from drug use and not a psychotic disorder. Of course, dual diagnoses are also not uncommon, but psychiatrists would closely monitor the pt (if the patient complies once out of the hospital) during the beginning to be sure about dosage and side effects. He's probably see a psychiatrist weekly in the beginning (just for a 10-15 minute med check). I have no idea if there is a black market for risp. --if he stopped seeing the psychiatrist he could probably find it on the street or internet. I wouldn't want to be your mc, LOL.

This has all been taken into account. A lot of how things work depends as uch on the participation of the patient as it is those trying to help him.

As far as methadone... heroin addicts are treated with methadone. As are oxycontin addicts and many other addicts. In drug therapy, methadone is administered to hardcore addicts who have been shooting/doing drugs for a prolonged period of time. My MC is one of those addicts - he needs the drug to stop using heroin... methadone is not his drug of choice. This is methadone's intended use. It's street use has nothing to do with my story. It's being used properly by health care professionals and administered to him in a daily dose by the staff.

My MC is a heroin addict with schizophrenia, and he's only just found that out. How many schizophrenics willingly share that information right off the bat? With anyone? It's not exactly a conversation starter and when you're a junkie, you think you can handle just about any drug on the planet.

Drug therapy mandated by the court system has nothing to do with the mental health professional he sees regularly for his other problems. He has only a few visits with her before he goes after some heroin and fails his next drug test. Long enough for her to start him on risperidone, but not long enough for him to be away from his cravings for heroin. At this point, he's still only on probation. When he gets caught failing the test, they send him to the facility. She only hears he's in the center when the reaction occurs - she contacts the center he's in and explains the risperadone. So if my MC doesn't tell the rehab center he's recently started risperidone, they have no way of knowing. This is the state system I'm writing about... not some cushy optional place you can check in and out for yourself. My MC doesn't do the rehab, he goes to prison for a probation violation. This is his last second chance. He already had the chance to try the NA and AA meetings, outpatient facilities, sponsoring and daily reports. He failed the drug test and goes into court mandated intensive rehab before his next office visit with his doctor.

I have my story figured out, I promise. That's not exactly what I needed help with. But thanks for being concerned - I have all my I-s crossed and my Ts dotted. ;)

Boron: Thank you. That is exactly what I needed. Layman's terms. One site said this could possibly lead to death... I'm assuming the increased heart beat could elevate to a heart attack? Cardiac arrest?

EFCollins
02-26-2011, 07:39 PM
Ahh, okay, I was unaware the 'metabolism' could be used in that context.

It just means that the rate at which the body processes the methadone, I am unclear whether they are referring to how quickly the methadone takes effect or how quickly the body purges methadone, but I am fairly sure it is the latter. That would mean the methadone stays in the system much longer.

Prolonging the QT interval creates a risk of arrhythmia which can lead to cardiac arrest.

I am no expert, I am just good at internet research. I hope that was some help.

The wikipedia article on QT interval was helpful to me. http://en.wikipedia.org/wiki/QT_interval

It was, thank you. And you preemptively answered my question in the above post. :)


DJ is correct
This could lead to accumulation of methadone in the body.

Yep. Methadone is a baaaad drug. I hate it - with a passion. And I have my reasons. It's a useless... just never mind. I hate methadone. Hate it. It killed my best friend and one of the only cousins I had that I gave a damn about... and I hate it.

So now I'll go see what I can find out about methadone accumulation in the body.


Thank you everyone! :)

boron
02-26-2011, 08:01 PM
. I'm assuming the increased heart beat could elevate to a heart attack? Cardiac arrest?Yes.

Methadone typically (but not exclusively) causes torsades de pointes ventricular tachycardia, which can:
- sometimes resolve on its own
- be treated by specific drugs for this type of tachycardia, and the patient is rescued without consequences. A critical point is that a doctor performs an ECG before starting with treatment to detect this exact type of arrhythmia, and use specific drugs, since the regular drugs for tachycardia may actually kill the patient.
- may develop into a ventricular fibrillation (a high frequency ventricular flutter), which causes cardiac arrest and is deadly in a large percent if not treated immediately by defibrillator and/or specific drugs. If treated successfully, the patient may have no consequences.
- fibrillation may develop into a heart attack, which can be anything from mild (to survive with a chronic heart failure of various extent) to deadly. A heart attack is usually associated with a severe chest pain. Heart attack by itself usually does not cause uncounsciousness, but this could occur during the preceding arrhythmia and impaired circulation.

In summary, torsades de pointes ventricular tachycardia is often deadly, so a quick diagnosis and treatment in the right order are necessary. Death can occur during the attack of arrhythmia or heart attack, or later (hours, days, weeks) from the consequences of the heart attack.

EFCollins
02-26-2011, 08:16 PM
Yes.

Methadone typically (but not exclusively) causes torsades de pointes ventricular tachycardia, which can then:
- resolve on its own
- be treated by specific drugs for this type of tachycardia, and the patient is rescued without consequences. A critical point is that a doctor performs an ECG before starting with treatment to detect this exact type of arrhythmia, and use specific drugs, since the regular drugs for tachycardia may actually kill the patient.
- this tachycardia may develop into a ventricular fibrillation (high frequency ventricular flutter), which is deadly in a large percent if not treated immediately by defibrillator and/or specific drugs.
- the result of tachycardia or fibrillation may be a heart attack, which can be anything from mild (to survive with a chronic heart failure of various extent) to deadly.

In summary, torsades de pointes ventricular tachycardia is often deadly, so a quick diagnosis and treatment in the right order are necessary. Death can occur during the attack of arrhythmia or heart attack, or later (hours, days, weeks) from consequences of the heart attack.

And if the staff of the health center dosing him daily with methadone is totally unaware of the rispiradone, they wouldn't know how to treat him... they would understand he was having a heart attack, but not that it was medicinally induced. Hmm. A rehab center has doctors on staff... would they immediately understand what's going on? And how would they treat that?

Sorry... these are questions for me to research about.... not ones I'm asking you guys.

boron
02-26-2011, 08:36 PM
I believe doctors dealing with methadone should know exactly how to treat a patient with arrhythmia. It is methadone that causes torsade de pointes ventricular tachycardia and doctors would know this. It is possible they would not give him methadone any more after this arrhythmia, EDIT: since it is not necessary dose dependent - it may occur even after a small dose of methadone. Explanation here (http://absolutewrite.com/forums/showpost.php?p=5875188&postcount=18)

Risperidone alone can also cause this arrhythmia, but in your case it more likely just ads to the harmful effect of methadone. Risperidone alone or in combination with methadone can cause this arrhythmia, but not always. This arrhythmia is actually quite rare.

EFCollins
02-26-2011, 11:31 PM
And with both factors, this likelihood increases? I would think so...

Thank you! You've been a huge help.

boron
02-27-2011, 12:40 AM
On the drugs.com (http://www.drugs.com/drug-interactions/methadone-with-risperidone-1578-0-2019-0.html) website it says:
"Theoretically, coadministration [of methadone] with other agents that can prolong the QT interval may result in additive effects and increased risk of ventricular arrhythmias including torsade de pointes and sudden death."

Qn Rxlist (http://www.rxlist.com/dolophine-drug.htm) it says:
"Extreme caution is necessary when any drug known to have the potential to prolong the QT interval is prescribed in conjunction with methadone."

From what I understand, the above warnings arise from the theoretical possibility of summarizing harmful effects of both medications, rather than from practical experience.

kathleea
02-27-2011, 01:11 AM
Lots of good info here. I know that on the inpatient psych unit I work on (I am a Psychiatric NP for my day job) we do EKG's for anyone on the antipsychotics not just risperdal. We don't see too much substance abuse so I have limited experience with it.

boron
02-28-2011, 07:57 PM
I need to correct myself.

Various online articles, like this one (http://www.drugs.com/drug-interactions/methadone-with-risperidone-1578-0-2019-0.html) state that a "very-high dose methadone" can cause torsades de pointes tachycardia, so not likely "even a small dose", like I said previously. Besides that, the presence of risk factors, like certain genetic diseases or hypokalemia were often documented in patients taing methaone and having this arrhythmia. I can't say if a doctor wold prescribe methadone again at some time after the arrhythmia episode, but investigations to find risk factors would be likely performed.

EFCollins
03-01-2011, 01:05 AM
So. MC goes to psych secretly. Is given rispiradone. He is doing drug court. Does heroin. (need to see how rispiradone would act with heroin a little more in depth) Fails drug test. Goes to an intensive rehab. He does not share the fact that he is on rispiridone.

Given that he is a 10 year plus heroin user, they would absolutely give a high dose of methadone. That's what his body would need.

How long would it take for the drugs to react? That is one thing I haven't found in my research. I want him to have the "episode" before anyone at the rehab knows he's on rispiradone. I'm sure they would recognize it as a drug interaction - which might keep the sudden death factor at bay. Resuscitation? Could work.

I wish I was already in college. But I'm not writing this book in two years when I start learning about Schizophrenia. I'm getting my masters in psychology. :)

Given that my MC is a hardcore, 10 yr. plus addict, they may try him on soboxone after the reaction, but I doubt it. I'd have to research soboxone in conjunction with rispiradone and methadone.

Maybe I should visit the local rehab and see if they'll talk to me there. They should.

Sorry, I'm taking notes in the forum! LOL!

GeorgeK
03-01-2011, 06:46 AM
MC goes to the hospital for an overdose on heroin. He is held for x amount of days, psych eval because the delusions, hallucinations (audible and visual) continue even after he is given adrenaline and time to come down from his high. The doctors prescribe risperidone.

Either I've missed something or your reading might be out of date. (Or I could be out of date, since I retired 5 years ago) If he did not respond to narcan and they had to give him epinephrine, he'd be on a monitored cardiac bed, not in a psych unit or rehab. The Psychiatrists and Psychologists don't want high risk cardiac patients in their wards, and if they have to give you epi for any reason, you are high risk for at least a day or two.

AngelRoseDarke
03-01-2011, 09:43 AM
Either I've missed something or your reading might be out of date. (Or I could be out of date, since I retired 5 years ago) If he did not respond to narcan and they had to give him epinephrine, he'd be on a monitored cardiac bed, not in a psych unit or rehab. The Psychiatrists and Psychologists don't want high risk cardiac patients in their wards, and if they have to give you epi for any reason, you are high risk for at least a day or two.

In the hospital I worked at they would have held the patient in a monitored cardiac bed and the psych eval would have been done there to determine need to transfer to psych ward or rehab after discharge from the cardiac floor.

boron
03-01-2011, 03:15 PM
Risperidone prolongs QT interval, what by itself does not cause any symptoms. Heroin is not on the list of medications that prolong QT interval (http://www.azcert.org/medical-pros/drug-lists/bycategory.cfm#), also I did not find any reports about heroin causing torsades de pointes tachycardia, so, concluding from this, risperidone + heroin would not likely cause arrhythmia, but could possibly summarize certain effects of both, like respiratory depression (dependent on the heroin and risperidone dose). By the way, risperidone may be actually used instead of methadone to prevent heroin withdrawal symptoms.

Heroin relaxing/drowsing effect lasts for only about an hour. Withdrawal effects (anxiety, sleeplessness...) may occur few hours after the last dose, peak between 48-72 hours and may last for about a week (or longer).

A low dose of methadone (like 30 mg) is given to the first time methadone users (http://www.rxlist.com/dolophine-drug.htm) and the dose may be slowly increased and, I guess, ECG is monitored in certain intervals. But you may ask some rehab doctor, is it likely that a very high dose of methadone (probably over 200 mg daily would be needed to cause arrhythmia) would be given to a patient with a strong withdrawal reaction. Arrhythmia may occur at any given time (days..) after any of very high doses of methadone, let's say 40 minutes after an intravenous injection, or 90 minutes after oral methadone (intravenous methadone starts to be effective in 10-20 minutes after administration, and oral methadone in 30-60 minutes). The effect of one dose lasts 6-8 hours, so four daily doses are likely.

It is not that risperidone ad methadone "react"; it is about the cumulative effect of both medications on the prolongation of the QT interval, so it all depends on the doses of both drugs. I believe that when a torsades de pointes tahycardia would be diagnosed, doctors would assume it was caused solely by methadone. They would test his blood for hypokalemia before starting the treatment, and later they might look for eventual contributing factors, such as genetically prolonged QT interval, and ask him if he takes any other drugs. Please note that methadone is not a treatment for heroin withdrawal, but only helps to overcome withdrawal symptoms. To correct dangerous side effects of heroin, like respiraory depression, other drugs (adrenalin) are necessary.

Suboxone could be given to overcome heroin withdrawal symptoms instead of methadone, but not to treat arrhythmia caused by methadone. Torsades de pointes tachycardia is treated by specific drugs (magnesium, beta blockers..) or, when it develops into a fibrillation, by a defibrillator. Resuscitation would be used only when the heart would actually stop (not even arrhythmic pulse detected by ECG).

EFCollins
03-03-2011, 10:43 PM
Either I've missed something or your reading might be out of date. (Or I could be out of date, since I retired 5 years ago) If he did not respond to narcan and they had to give him epinephrine, he'd be on a monitored cardiac bed, not in a psych unit or rehab. The Psychiatrists and Psychologists don't want high risk cardiac patients in their wards, and if they have to give you epi for any reason, you are high risk for at least a day or two.

I didn't say they'd keep him in a psych unit, but that he would be evaluated. And sadly, I didn't draw on that aspect of it from reading. Personal experience there, though not with heroin. And not me.

EFCollins
03-03-2011, 10:46 PM
Risperidone prolongs QT interval, what by itself does not cause any symptoms. Heroin is not on the list of medications that prolong QT interval (http://www.azcert.org/medical-pros/drug-lists/bycategory.cfm#), also I did not find any report about heroin causing torsades de pointes tachycardia, so, concluding from this, risperidone + heroin would not likely cause arrhythmia, but could possibly summarize certain effects of both, like respiratory depression (dependent on the heroin and risperidone dose). By the way, risperidone may be actually used instead of methadone to prevent heroin withdrawal symptoms.

Heroin relaxing/drowsing effect lasts for only about an hour. Withdrawal effects (anxiety, sleeplessness...) may occur few hours after the last dose, peak between 48-72 hours and may last for about a week (or longer).

A low dose of methadone (like 30 mg) is given to the first time methadone users (http://www.rxlist.com/dolophine-drug.htm) and the dose may be slowly increased and, I guess, ECG is monitored in certain intervals. But you may ask some rehab doctor, is it likely that a very high dose of methadone (probably over 200 mg daily would be needed to cause arrhythmia) would be given to a patient with a strong withdrawal reaction. Arrhythmia may occur at any given time (days..) after any of very high doses of methadone administrations, let's say 40 minutes after an intravenous injection, or 90 minutes after oral methadone (intravenous methadone starts to be effective in 10-20 minutes after administration, and oral methadone in 30-60 minutes). The effect of one dose lasts 6-8 hours, so four daily doses are likely.

It is not that risperidone ad methadone "react"; it is about the cumulative effect of both medications on the prolongation of the QT interval, so it all depends on the doses of both drugs. I believe that when a torsades de pointes tahycardia would be diagnosed, doctors would assume it was caused solely by methadone. They would test his blood for hypokalemia before stating the treatment, and later they might look for eventual contributing factors, such as genetically prolonged QT interval and ask him if he takes any other drugs. Please note that methadone is not a treatment for heroin withdrawal, but only helps to overcome withdrawal symptoms. To correct dangerous side effects of heroin, like respiraory depression, other drugs (adrenalin) are necessary.

Suboxone could be given to overcome heroin withdrawal symptoms instead of methadone, but not to treat arrhythmia caused by methadone. Torsades de pointes tachycardia is treated by specific drugs (magnesium, beta blockers..) or, when it develops into a fibrillation, by a defibrillator. Resuscitation would be used only when the heart would actually stop (not even arrhythmic pulse detected by ECG).

Best. Info. Ever. I'm serious... this is extremely helpful to me. Thank you! You didn't have to take so much time for this and I appreciate it very much.

boron
03-03-2011, 11:51 PM
I'm about to edit it and sell it as a researched article :) .