Cytochrome P450 Testing In High-dose Opioid Patients

[Kyla]

http://www.practicalpainmanagement....chrome-p450-testing-high-dose-opioid-patients

Excerpt:

P450 Testing In High-dose Opioid Patients
Severe, chronic pain patients who seek opioid dosages above normal standards should now be tested for genetic cytochrome P450 deficiencies.

By Forest Tennant, MD, DrPH



While it is common knowledge that the cytochrome P450 (CYP450) enzyme system is critical for the metabolism of some opioids, genotype testing of pain patients for CYP450 polymorphism has not been generally recommended.1,2 This situation, however, may change as pain specialists begin to recognize that patients who require high doses of opioids may have a genetic defect that may affect their ability to metabolize these agents.

In the past, genotyping for CYP450 polymorphisms was not cost effective or convenient. However, testing technology, commercial availability, third-party reimbursement, and most of all, clinical understanding, have recently coalesced to make CYP450 genetic testing an essential component of high-dose opioid therapy. It is my recommendation, therefore, that patients who require more than 150 mg per day of morphine equivalents be tested for three specific CYP defects—2D6, 2C9, and 2C19.

To study the validity of genotype testing, I prospectively studied 66 patients on high-dose opioids in my pain clinic. The study found that the vast majority of these patients had CYP450 defects...

 

[Skippa]

Ooh hello, anyone know what else I can look out for that is symptomatic of CYP450 deficiencies without actually getting tested?

 

[cfs6691]

Shouldn't CFSsufferers who are intolerant to chemicals or have had an adverse reaction to medication eg antibiotics,anabolic or contraceptive steroids(such as myself)also be tested since the cytochrome p-450 enzymes break down medications and other chemicals that need to be eliminated from the body?I have had adverse reactions to antibiotics and to contraceptive steroids,I suspect that I and other CFSsufferers may have undiagnosed liver damage that affects the body's ability to eliminate xenobiotics.I am not insured and I cannot afford to have genetic testing done.I am also wondering if it would serve any purpose even if it turned out that I have a mutation or polymorphisms since researchers are focused on their ideas and theories.I would probably be able to announce it by starting a thread but unless there is some way of having testing done that is affordable to someone who does'nt have many resources I don't see the point unless soneone keeps track of those findings and follows up(eg liver biopsy since blood tests are not reliable in order to rule out liver disease/damage or other tests if genetic testing points out to another organ/system being affected).