Quote:
Originally Posted by pega
Do we have to remember the drug dosage numbers for FPGEE?
I'm talking about the dosage numbers on pharmacology sections of CPR?
I also asked one more question before and never got an answer.Here it is again:
Do we have to remember the hole drugs name wich has been listed on page 420 of CPR 6TH eddition?It,s all about Drug,Herb and food actions with CYP450.
Does anybody have an idea how we can remember them?
There is something similar on page 396 Table 17-1 .
I would appreciate it .
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Hi,
Concerning the drugs that induce or inhibit P45 enzymes,
Drugs that induce P450 are rare. Try to memorize them as groups. Usually Anti-epileptic drugs induce P450 enzymes . They include Barbiturates, Phenytoin and Carbamazepine and Primidone .
Another very important drug is Rifampicin.
These four drugs are the most important . They affect CYP3A4 which is the most important enzyme.
Cigarette smoking is important for only few drugs namely TCA , warfarin and Theophylline metabolism of which relies on CYP1A2.
Alcohol is important for only few drugs too , Acetaminophen , halothane and Enflurane , metabolism of which relies on CYP2E1.
St John's wort , is important for drugs being metabolised by CYP3A4 or CYP2C9.
Try to memorize all CYP3A4 substrates . Important substrates include Ciclosporin , corticosteroids oral contraceptive and Amiodarone.
Also try to pick up the most important drugs. For example, it's very important to know which enzyme metabolises Oral contraceptives and which drugs affect this enzyme because a therapeutic failure due to enzyme induction would result in pregnancy which is a disaster. Ciclosporin is also an important example because therapeutic failure results in transplant rejection which is disastrous too. On the other hand you can ignore other drugs which has wide theraoeutic index for example or drugs where interaction wouldn't result in calamitous results.
Most drugs are usually metabolised by more than one enzyme of the P450 isoenzymes, so inhibition or induction of a single enzyme wouldn't have a potential effect. So Try to look at the list and pick up drugs that are metabolised by a single enzyme and memorize them. In such drugs interactions usually have sever results because there are no ways for the liver to compensate. That's why such drugs are the most important .
That's all you need to know about enzyme induction.
For enzyme inhibition , it's more difficult since there are many more.
Try to memorize them as groups . Anti-fungal drugs, antivirals, anti depressants ( SSRI ) ,antibacterials ( ciprofloxacin, iso niazid and metronidazole ) , GI drugs ( cimitidine and omeprazole ) , anti rheumatic drugs and cardio vascular drugs ( amiodarone , verpamil quinidine and diltiazem )
that's most of what you need to know. It didn't take me long to memorize them . just try to repeat and repeat . don't try to memorize them all on the same day because you won't . Just repeat . Classify them and read them every day .
hope this hepls
Cheers,