Medications

Overview

GenesFX Health provides gene testing for approximately 50% of currently prescribed medications. A person's genetic makeup plays an important role in how the body processes the medication. 

Genetic testing  can define metabolism status and can help doctors prescribe the right dose and determine if a particular drug is suitable .This area of medicine is known as pharmacogenomics. Pharmacogenomic testing can reduce the risk of side effects and sometimes tell if the drug will work in a particular patient or not. This provides a more presonalised approach to drug prescribing.

The test is evidence based and provides doctors with another tool that they can use in clinical decision-making by;

  • Finding the right drug and the right dose
  • Safer use of medications by minimising Adverse Drug Reactions
  • Improving therapeutic response to prescribed medications
  • Quality use of medicines

Substrates

Below is a list of drugs (substrates) that are metabolised by specific CYP450 enzymes.  

CYP2C19                    

CYP2C9               

CYP2D6                                    

Proton Pump Inhibitors: NSAIDs:
diclofenac      
Ibuprofen
Antidepressants:
amitriptyline
esomeprazole clomipramine
lansoprazole indomethacin dothiepin
omeprazole meloxicam doxepin
pantoprazole naproxen duloxetine
rabeprazole piroxicam fluoxetine
    fluvoxamine
Anti-epileptics: Angiotensin II imipramine
diazepam Blockers: mirtazapine
phenobarbitone irbesartan nortriptyline
  losartan paroxetine
Antidepressants:   trimipramine
amitriptyline Sulfonylureas: venlafaxine
citalopram glibenclamide  
clomipramine gliclazide Antipsychotics:
dothiepin glimepiride aripiprazole
doxepin glipizide chlorpromazine
escitalopram   haloperidol
fluvoxamine Others: risperidone
imipramine celecoxib zuclopenthixol
moclobemide fluoxetine  
sertraline fluvastatin Beta Blockers:
trimipramine montelukast carvedilol
  phenobarbitone metoprolol
Others: phenytoin propranolol
clobazam primidone timolol
clopidogrel rosiglitazone  
cyclophosphamide
flunitrazepam
warfarin
zafrilukast
Opioid
Analgesics:
gliclazide   codeine
indomethacin   oxycodone
nelfinavir   tramadol
nilutamide    
phenytoin   Others:
primidone   atomoxetine
proguanil   chlorpheniramine
propranolol   dexamphetamine
teniposide   dextromethorphan
    flecainide
    metoclopramide
    ondansetron
    perhexiline
    proguanil
    promethazine
    tamoxifen
    tropisetron

Inhibitors

Inhibitors bind to the enzyme and reduce the enzyme activity in metabolising the substrate (drug). A strong inhibitor greatly decreases the amount of drug metabolised. This may lead to an increase in side effects for active drugs and a decrease in effect for pro-drugs. Weak inhibitors have a minimal effect on this process; therefore they are not included in the list below.

Strong and moderate inhibitors are listed below according to the specific enzyme they inhibit:  

CYP2C19

CYP2C9

CYP2D6

dothiepin
fluconazole
chlorpromazine
fluconazole
ibuprofen
fluoxetine
fluvoxamine
indomethacin
paroxetine
isoniazid
ketoconazole
terbinafine
modafinil
piroxicam
amiodarone
omeprazole
sildenafil
cimetidine
ticlopidine
sulfamethoxazole
clomipramine
voriconazole
voriconazole
diphenhydramine
cimetidine
amiodarone
duloxetine
fluoxetine
fenofibrate
haloperidol
ketoconazole
fluvastatin
imipramine
lansoprazole
losartan
ketoconazole
rabeprazole
omeprazole
metoclopramide
sertraline
pantoprazole
promethazine
 
warfarin
sertraline
 
zafirlukast
ticlopidine

Inducers

Inducers stimulate the production of an enzyme which increases the rate of metabolism of a drug.  Examples of enzyme inducers are listed below:

CYP2C19

CYP2C9

CYP2D6

carbamazepine
carbamazepine
          -
phenytoin
phenobarbitone
          -
prednisone
phenytoin
          -
rifampicin
primidone
          -
 
rifampicin
 

This information is not intended to be a substitute for medical advice.