Cytochrome P450 : Alphabetical drug list
Quick Links:
1A2 2C9 2C19 2D6 2E1 3A4
Have you read our disclaimer?
Drug CYP interaction Clinical consequences
Macrolides (esp erythromycin, troleandromycin)
(clarithromycin, flurithromycin, midecamycin, midecamycin acetate, josamycin and roxithromycin rarely cause trouble [Drug Saf 1995 Aug;13(2):105-22];
azithromycin, dirithromycin, rikamycin, spiramycin do NOT inactivate 3A4)
CYP3A4 : INHIBIT erythromycin & troleandromycin interact with eg. carbamazepine, cyclosporin, terfenadine, astemizole, theophylline [Drug Saf 1995 Aug;13(2):105-22]
maprotiline (antidepressant) 2D6 : metabolism
(possibly also by 2C9 )
interaction potential;
poor metabolisers have high levels and vice versa.
mefenamic acid 2C9 : metabolism ?
meperidine : see pethidine
(S)-mephenytoin CYP2C19 : metabolism ?
(R)-mephobarbital (See also Barbiturates) 2C19 : substrate ?
(S)-mephobarbital (See also Barbiturates) CYP2B6 : metabolism ?
mepyramine (1st generation antihistamine) 2D6 : INHIBITS (Ki ~ 34 nM) ?
mequitazine (selective H1 receptor blocker) 2D6 : METABOLISM [J Pharmacol Exp Ther 1998 Feb;284(2):437-42] (possibly inhibits 3A4 too) ?
mestranol 2C9 : metabolism (to ethinylestradiol) potentially ineffective with 2C9 inhibitors.
methadone 3A4 : substrate interactions with e.g. rifampicin, ?diazepam, nevirapine
methoxsalen 2A6 : potent INHIBITOR ?
1A2 : inhibits ?
methoxyamphetamine 2D6 : metabolism ? (cf. amphetamine)
methoxyflurane 2E1 : metabolism ?
methylenedioxymetamphetamine : see amphetamine
metoclopramide ?? 2D6 (is there any information out there?) ?
(S)-metoprolol (See also beta blockers) 2D6 : metabolism may be clinically significant interaction with 2D6 inhibitors, e.g. quinidine, some SSRIs eg. fluoxetine, norfluoxetine and paroxetine
metronidazole CYP2C9 : INHIBITS ?
3A4 : ? inhibits ?
metyrapone 3A4 : induces ?
CYP11B1 : INHIBITS inhibition of cortisol synthesis ('adrenal inhibition')
mexiletine CYP2D6 : METABOLISM low activity causes toxicity (arrhythmias)
2D6 : inhibits ? interaction with e.g. metoprolol
CYP1A2 : substrate rifampicin, phenytoin, tobacco smoking increase removal; ciprofloxacin & propafenone slow removal; [Clin Pharmacokinet 1999 Nov;37(5):361-84]
CYP1A1 (Ki 0.28) , and ? 1A2 : INHIBITION potential for eg. theophylline toxicity [Eur J Drug Metab Pharmacokinet 1999 Apr-Jun;24(2):149-53]
(S-), (R-) mianserin CYP2D6 : metabolism ( S- ) moderate (or greater) clinical significance; interaction with thioridazine
3A4 : metabolism of both enantiomers interaction with e.g. carbamazepine
mibefradil (selective T-type calcium channel blocker) 3A4 : INHIBITS (potent, irreversible) ? interaction with eg statins (See
[Br J Clin Pharmacol 1999 Mar;47(3):291-8] ), cisapride, and cyclosporin [Nephrol Dial Transplant 1998 Jul;13(7):1787-91]
2D6 : inhibits ?
1A2 : inhibits ?
miconazole 2E1 : inhibits (Ki ~ 4-20 µM) [Xenobiotica 1998 Mar;28(3):293-301] ?
2C9 : INHIBITS See reference for fluconazole!
mifepristone 3A4 : INHIBITS (mechanism-based inactivator) ?
mirtazapine (NaSSA = noradrenergic specific serotonergic antidepressant, NOT SSRI) NO significant effect on 2D6, 1A2, 3A4 [Drugs 1999 Apr;57(4):607-31], [Depress Anxiety 1998;7 Suppl 1:24-32] A good interaction profile
midazolam See also benzodiazepines (3A4/5)
CYP3A5 : METABOLISM interaction with eg cimetidine, .. other 3A4 inhibitors (excessive sedation), also itraconazole, grapefruit juice.
minaprine 2D6 : metabolism ?
moclobemide 2C19 : substrate cimetidine inhibits elimination [Clin Pharmacokinet 1995 Nov;29(5):292-332]
2D6 : INHIBITS (may also inhibit 2C19, 1A2) ?
montelukast 3A4 : metabolism ? nil
2C9 : metabolism ? nil

Quick Links:
1A2 2C9 2C19 2D6 2E1 3A4

Page author: jo@anaesthetist.com Last update: 2000-6-22