For those of you embarking on a journey with Daclatasvir please be aware that this medication is metabolised by an enzyme called CYP3A4.
There are some other medications that inhibit this enzyme (resulting in higher Daclatasvir levels) and other medications that induce (increase) this enzyme (resulting in lower Daclatasvir levels).
Dose reduction (to 30 mg) is suggested for people who are taking medications that are strong inhibitors of CYP3A4. Don't worry if dose reduction is suggested, because the Daclatasvir is not metabolised as well you will probably still have higher than normal levels.
Inhibitors of CYP3A4 include (please note this is not an exhaustive list):
- Aminodarone
- Anastrozole
- Azithromzcin
- Cannabinoids
- Cimetidine
- Clarithromycin
- Clotrimazole
- Cyclosporine
- Danazol
- Delavirdine
- Dexamethasone
- Diethyldithiocarbamate
- Diltiazem
- Dirithyromycin
- Disulfiram
- Entacapone (high dose)
- Erythromycin
- Ethinyl estradiol
- Fluconazole
- Fluoxetine
- Fluvoaxamine
- Gestodene
- Grapefruit juice
- Indinavir
- Isoniazid
- Ketoconazole
- Metronidazole
- Mibefradil
- Miconazole
- Nefazodone
- Nelfinavir
- Nevirapine
- Norfloxacin
- Norfluoxetine
- Omeprazole
- Oxiconazole
- Paroxetine (weak)
- Propoxyphene
- Quinidine
- Quinine
- Quinupristine and dalfopristin
- Ranitidine
- Ritonavir
- Saquinavir
- Sertindole
- Sertraline
- Troglitazone
- Troleandomycin
- Valproic acid
This list includes common antidepressants, ingredients in the contraceptive pill and even Grapefruit Juice.
Here is the FDA overview on CYP3A4 - Check table 5 (in vivo)* - and note than a strong inhibitor is of course more of a worry than a weak one.
www.fda.gov/Drugs/DevelopmentApprovalPro...beling/ucm093664.htm
* Studies that are
in vivo (Latin for
"within the living") are those in which the effects of various biological entities are tested on whole, living organisms usually animals including humans, and plants as opposed to a partial or dead organism, or those done
in vitro (
"within the glass")
