museabuse

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Just curious,

What are some common drug interactions that you always call the Dr?
 

FruitFly

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I've been calling to change a lot of photosensitizing antibiotics lately. I'd say it varies a lot for the most part.

edit: oops, I guess you wanted drug-drug interactions, my bad.
 

npage148

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bactrim and warfarin

I also love calling dentists to tell them they gave a lortab script to a pt on MSIR and Mscontin. It happens alot and they are always more than happy to cancel it
 

BMBiology

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bactrim and warfarin

I also love calling dentists to tell them they gave a lortab script to a pt on MSIR and Mscontin. It happens alot and they are always more than happy to cancel it
I agree with your action but I dont want people to think there is a dangerous drug-drug interaction between lortab and morphine per say. There may be an additive effect when two opiods are prescribed. It is fine if the prescriber wants to change or not add another opioid and caution should be used when an opioid is prescribed but there is no max dose for opioids, unless it also contains another ingredient such as APAP. Just remember that many patients need more than one opioid to control their pain.
 

njac

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I agree with your action but I dont want people to think there is a dangerous drug-drug interaction between lortab and morphine per say. There may be an additive effect when two opiods are prescribed. It is fine if the prescriber wants to change or not add another opioid and caution should be used when an opioid is prescribed but there is no max dose for opioids, unless it also contains another ingredient such as APAP. Just remember that many patients need more than one opioid to control their pain.
We were taught that >1 opiate is not any more efficacious for pain control than only 1, and to increase the dose of the existing drug and make sure they're using rescue doses when needed.
 

BMBiology

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We were taught that >1 opiate is not any more efficacious for pain control than only 1, and to increase the dose of the existing drug and make sure they're using rescue doses when needed.
That is true. Some patients need a long acting opioid for maintenance and a fast acting opioid for acute pain. However, it really varies among patients. There's no one rule for every patients.

For example, a patient may do well on methadone but when dose >200 mg/day, the risk for QT prolongation significantly increases. So for this patient, it may better to prescribe another opioid than to increase the methadone dose above 200mg/day.

It's not a matter of drug drug interaction. It is a matter of risk vs. benefits.
 

Pharmavixen

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I think you're partly right; in my experience, polypharmacy is more common than an intelligent use of more than one opioid. However, methadone also is an antagonist at the NMDA receptors and is more effective for neuropathic pain.

But the prescribing of oxycodone has gone up 400% in the US in the past ten years. Americans are the #1 users of opioids worldwide. Were there that many people in severe intractable pain B4?

Back O/T: as a methadone dispenser, I'm always phoning drs re: drug interactions. Methadone drs are fairly up on the interactions, but other MDs the pts see may not be. Methadone is a substrate for CP450 3A4, which is huge, so tons of drugs affect it, either raising or lowering its levels.

Recently I contacted public health about a methadone client started on rifampin. The guidelines where I work suggest methadone patients receive rifabutin instead, but it's not covered by Drug Benefit (like Medicaid), so they kept her on the rifampin, which potentiates the metabolism of the methadone. So...this lady experienced WD symptoms, and has relapsed into street drug use.
 

BMBiology

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Pharmavixem: since you are a methadone pharmacist, any recommendation on a good read on methadone?
 

aphistis

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bactrim and warfarin

I also love calling dentists to tell them they gave a lortab script to a pt on MSIR and Mscontin. It happens alot and they are always more than happy to cancel it
I'd be glad for the phone call.

I don't stack narcotics. If I'm writing pain meds for someone who's already on hydrocodone or stronger, they get ibuprofen (if it's OK for them) or else just instructions to keep taking their existing pain meds as scheduled and to call if they're having problems. I've gotten very few phone calls.
 

tussionex

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bactrim and warfarin

I also love calling dentists to tell them they gave a lortab script to a pt on MSIR and Mscontin. It happens alot and they are always more than happy to cancel it
most dentists i know in my area don't prescribe more than a few days' worth of vicodin, etc, so honestly, if i had a patient that i knew was stabilized on MSContin or the like [like an RA patient that i had....took a boatload of the stuff] i really wouldnt have a problem with letting him/her have the vicodin....OF COURSE, with some counseling and the recommendation that an NSAID would probably help dental pain just as well if not better.

i don't think a coupla vicodin in an opioid tolerant patient will create that much of an additive effect.

personally, for all my dental work i've had, root canals, extractions...i've always found that plain old motrin does the trick just fine!
 

npage148

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I guess my direction was not the DDI per say, but that the pt is usually a drug seeker going to dentists to get more narcotics.

If they had legitimate dental pain why would they want/need hydrocodone when they had a stock of MSIR or another strong fast acting opoid
 

BMBiology

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I guess my direction was not the DDI per say, but that the pt is usually a drug seeker going to dentists to get more narcotics.

If they had legitimate dental pain why would they want/need hydrocodone when they had a stock of MSIR or another strong fast acting opoid
Just want to clarify in terms of potency, hydrocodone PO = morphine PO.
 

b*rizzle

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Back on topic: Lipitor and ketoconazole/clarithromycin. We always call to verify & also let the doctor know we've told the patient to stop their Lipitor while on either.
 

Pharmavixen

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Pharmavixem: since you are a methadone pharmacist, any recommendation on a good read on methadone?
I usually recommend the College of Physicians and Surgeons of Ontario clinical practice guidelines, like Methadone for Pain, or Methadone Maintenance as an overview. Though the guidelines are intended for doctors practising in Ontario, there's lots of good general info.