Appendix 1: Medications Assessed for Dosing Problems and Drug-Drug Interactions

Appendix 1: Medications assessed for dosing problems and drug-drug interactions

Drug / How identified for inclusion / Drug dosing (general) / Dosing / use in renal impairment / Dosing / use in hepatic impairment / Drug-drug interactions – any type (e.g. pharmacokinetic or pharmacodynamic) / Drug-drug interactions (P450-mediated only)
ACETAMINOPHEN / Common drugs in VA / x / x / x / x
Acyclovir / Additional drugs with renal dosing criteria / x
ALENDRONATE / Common drugs in VA / x / x / x / x
ALLOPURINOL / Common drugs in VA / x / x / x / x
ALPRAZOLAM / Common drugs in VA / x / x / x / x
ALPROSTADIL / Common drugs in VA / x / x / x / x
Amantadine / Additional drugs with renal dosing criteria / x
AMIODARONE / Common drugs in VA / x / x / x / x
AMITRIPTYLINE / Common drugs in VA / x / x / x / x
AMLODIPINE / Common drugs in VA / x / x / x / x
amodiaquine / Additional drugs with CYP-450 interactions / x
AMOXICILLIN / Common drugs in VA / x / x / x / x
AMOXICILLIN/CLAVULANATE / Common drugs in VA / x / x / x / x
aniline / Additional drugs with CYP-450 interactions / x
anisindione / Additional drugs with drug-drug interactions / x
aripiprazole / Additional drugs with CYP-450 interactions / x
ASCORBIC ACID / Common drugs in VA / x / x / x / x
ASPIRIN / Common drugs in VA / x / x / x / x
astemizole / Additional drugs with CYP-450 interactions / x
ATENOLOL / Common drugs in VA / x / x / x / x
ATORVASTATIN / Common drugs in VA / x / x / x / x
azathioprine / Additional drugs with drug-drug interactions / x
AZITHROMYCIN / Common drugs in VA / x / x / x / x
BACLOFEN / Common drugs in VA / x / x / x / x
benzene / Additional drugs with CYP-450 interactions / x
BISACODYL / Common drugs in VA / x / x / x / x
BUPROPION / Common drugs in VA / x / x / x / x
buspirone / Additional drugs with CYP-450 interactions / x
CALCIUM CARBONATE / Common drugs in VA / x / x / x / x
CALCIUM/VITAMIN D / Common drugs in VA / x / x / x / x
carbamazepine / Additional drugs with CYP-450 interactions / x
CARBIDOPA/LEVODOPA SR / Common drugs in VA / x / x / x / x
CARVEDILOL / Common drugs in VA / x / x / x / x
CELECOXIB / Common drugs in VA / x / x / x / x
CEPHALEXIN / Common drugs in VA / x / x / x / x
CHLORPHENIRAMINE / Common drugs in VA / x / x / x / x
Chlorpropamide / Additional drugs with renal dosing criteria / x
chlorzoxazone / Additional drugs with CYP-450 interactions / x
CIMETIDINE / Common drugs in VA / x / x / x / x
CIPROFLOXACIN / Common drugs in VA / x / x / x / x
cisapride / Additional drugs with CYP-450 interactions / x
CITALOPRAM / Common drugs in VA / x / x / x / x
clarithromycin / Additional drugs with CYP-450 interactions / x
clomipramine / Additional drugs with CYP-450 interactions / x
CLONIDINE / Common drugs in VA / x / x / x / x
CLOPIDOGREL / Common drugs in VA / x / x / x / x
clozapine / Additional drugs with CYP-450 interactions / x
codeine / Additional drugs with CYP-450 interactions / x
CODEINE/ACETAMINOPHEN / Common drugs in VA / x / x / x / x
COLCHICINE / Common drugs in VA / x / x / x / x
CYANOCOBALAMIN ORAL / Common drugs in VA / x / x / x / x
cyclobenzaprine / Additional drugs with CYP-450 interactions / x
CYCLOBENZAPRINE IR / Common drugs in VA / x / x / x / x
cyclophosphamide / Additional drugs with CYP-450 interactions / x
cyclosporine / Additional drugs with CYP-450 interactions / x
desipramine / Additional drugs with CYP-450 interactions / x
dextromethorphan / Additional drugs with CYP-450 interactions / x
DEXTROMETHORPHAN/GUAIFENESIN SYRUP / Common drugs in VA / x / x / x / x
diazepam / Additional drugs with CYP-450 interactions / x
diclofenac / Additional drugs with CYP-450 interactions / x
dicumarol / Additional drugs with drug-drug interactions / x
DIGOXIN / Common drugs in VA / x / x / x / x
dihydroergotamine / Additional drugs with drug-drug interactions / x
DILTIAZEM / Common drugs in VA / x / x / x / x
DIPHENHYDRAMINE / Common drugs in VA / x / x / x / x
disulfiram / Additional drugs with CYP-450 interactions / x
DOCUSATE / Common drugs in VA / x / x / x / x
DONEPEZIL / Common drugs in VA / x / x / x / x
DOXAZOSIN / Common drugs in VA / x / x / x / x
doxepin / Additional drugs with CYP-450 interactions / x
DOXYCYCLINE / Common drugs in VA / x / x / x / x
duloxetine / Additional drugs with CYP-450 interactions / x
efavirenz / Additional drugs with CYP-450 interactions / x
ENALAPRIL / Common drugs in VA / x / x / x / x
enflurane / Additional drugs with CYP-450 interactions / x
enoxacin / Additional drugs with CYP-450 interactions / x
EPOETIN ALFA / Common drugs in VA / x / x / x / x
ergotamine / Additional drugs with drug-drug interactions / x
ERYTHROMYCIN / Common drugs in VA / x / x / x / x
ethanol / Additional drugs with CYP-450 interactions / x
ethinyl estradiol / Additional drugs with drug-drug interactions / x
ETODOLAC / Common drugs in VA / x / x / x / x
EZETIMIBE / Common drugs in VA / x / x / x / x
FELODIPINE / Common drugs in VA / x / x / x / x
FERROUS SULFATE / Common drugs in VA / x / x / x / x
FEXOFENADINE / Common drugs in VA / x / x / x / x
FINASTERIDE / Common drugs in VA / x / x / x / x
flecainide / Additional drugs with CYP-450 interactions / x
fluconazole / Additional drugs with CYP-450 interactions / x
FLUOXETINE / Common drugs in VA / x / x / x / x
fluvastatin / Additional drugs with CYP-450 interactions / x
fluvoxamine / Additional drugs with CYP-450 interactions / x
FOLIC ACID / Common drugs in VA / x / x / x / x
FOSINOPRIL / Common drugs in VA / x / x / x / x
FUROSEMIDE / Common drugs in VA / x / x / x / x
GABAPENTIN / Common drugs in VA / x / x / x / x
ganciclovir / Additional drugs with drug-drug interactions / x
gatifloxacin / Additional drugs with CYP-450 interactions / x
GEMFIBROZIL / Common drugs in VA / x / x / x / x
gemifloxacin / Additional drugs with CYP-450 interactions / x
gleevec / Additional drugs with CYP-450 interactions / x
GLIPIZIDE / Common drugs in VA / x / x / x / x
GLYBURIDE / Common drugs in VA / x / x / x / x
grepafloxacin / Additional drugs with CYP-450 interactions / x
GUAIFENESIN / Common drugs in VA / x / x / x / x
haloperidol / Additional drugs with CYP-450 interactions / x
halothane / Additional drugs with CYP-450 interactions / x
HCTZ/TRIAMTERENE / Common drugs in VA / x / x / x / x
HYDRALAZINE / Common drugs in VA / x / x / x / x
HYDROCHLOROTHIAZIDE / Common drugs in VA / x / x / x / x
HYDROCODONE/ACETAMINOPHEN / Common drugs in VA / x / x / x / x
HYDROXYZINE / Common drugs in VA / x / x / x / x
IBUPROFEN / Common drugs in VA / x / x / x / x
ifosfamide / Additional drugs with CYP-450 interactions / x
imipramine / Additional drugs with CYP-450 interactions / x
indinavir / Additional drugs with CYP-450 interactions / x
INSULIN / Common drugs in VA / x / x / x / x
IRBESARTAN / Common drugs in VA / x / x / x / x / x
isocarboxazid / Additional drugs with drug-drug interactions / x
isoflurane / Additional drugs with CYP-450 interactions / x
isoniazid / Additional drugs with CYP-450 interactions / x
ISOSORBIDE DINITRATE / Common drugs in VA / x / x / x / x
ISOSORBIDE MONONITRATE / Common drugs in VA / x / x / x / x
itraconazole / Additional drugs with CYP-450 interactions / x
ketoconazole / Additional drugs with CYP-450 interactions / x
LANSOPRAZOLE / Common drugs in VA / x / x / x / x
LEVOFLOXACIN / Common drugs in VA / x / x / x / x
LEVOTHYROXINE / Common drugs in VA / x / x / x / x
LISINOPRIL / Common drugs in VA / x / x / x / x
lomefloxacin / Additional drugs with CYP-450 interactions / x
LORATADINE / Common drugs in VA / x / x / x / x
LORAZEPAM / Common drugs in VA / x / x / x / x
LOSARTAN / Common drugs in VA / x / x / x / x
LOVASTATIN / Common drugs in VA / x / x / x / x
MAGNESIUM CITRATE / Common drugs in VA / x / x / x / x
MAGNESIUM HYDROXIDE (MOM) / Common drugs in VA / x / x / x / x
MECLIZINE / Common drugs in VA / x / x / x / x
Memantine / Additional drugs with renal dosing criteria / x
Meperidine / Additional drugs with renal dosing criteria / x
mercaptopurine / Additional drugs with drug-drug interactions / x
mestranol / Additional drugs with drug-drug interactions / x
METFORMIN / Common drugs in VA / x / x / x / x
methadone / Additional drugs with CYP-450 interactions / x
methotrexate / Additional drugs with drug-drug interactions / x
methoxyflurane / Additional drugs with CYP-450 interactions / x
methylsergide / Additional drugs with drug-drug interactions / x
METOCLOPRAMIDE / Common drugs in VA / x / x / x / x
METOPROLOL / Common drugs in VA / x / x / x / x
METRONIDAZOLE / Common drugs in VA / x / x / x / x
mexiletine / Additional drugs with CYP-450 interactions / x
mibefradil / Additional drugs with CYP-450 interactions / x
midazolam / Additional drugs with CYP-450 interactions / x
montelukast / Additional drugs with CYP-450 interactions / x
MOXIFLOXACIN / Common drugs in VA / x / x / x / x
MULTIVITAMINS / Common drugs in VA / x / x / x / x
N,N-dimethyl formamide / Additional drugs with CYP-450 interactions / x
nabumetone / Additional drugs with CYP-450 interactions / x
NAPROXEN / Common drugs in VA / x / x / x / x
nefazodone / Additional drugs with CYP-450 interactions / x
nelfinavir / Additional drugs with CYP-450 interactions / x
NIACIN IR / Common drugs in VA / x / x / x / x
nifedipine / Additional drugs with CYP-450 interactions / x
NIFEDIPINE SR / Common drugs in VA / x / x / x / x
nisoldipine / Additional drugs with CYP-450 interactions / x
nitrendipine / Additional drugs with CYP-450 interactions / x
Nitrofurantoin / Additional drugs with renal dosing criteria / x
NITROGLYCERIN / Additional drugs with drug-drug interactions / x
NITROGLYCERIN SL TAB / Common drugs in VA / x / x / x / x
norfloxacin / Additional drugs with CYP-450 interactions / x
NORTRIPTYLINE / Common drugs in VA / x / x / x / x
NYSTATIN SUSP / Common drugs in VA / x / x / x / x
ofloxacin / Additional drugs with CYP-450 interactions / x
olanzapine / Additional drugs with CYP-450 interactions / x
OMEPRAZOLE / Common drugs in VA / x / x / x / x
ondansetron / Additional drugs with CYP-450 interactions / x
OXYBUTYNIN / Common drugs in VA / x / x / x / x
OXYCODONE / Common drugs in VA / x / x / x / x
paclitaxel / Additional drugs with CYP-450 interactions / x
pantoprazole / Additional drugs with CYP-450 interactions / x
PAROXETINE / Common drugs in VA / x / x / x / x
PENTOXIFYLLINE / Common drugs in VA / x / x / x / x
phenelzine / Additional drugs with drug-drug interactions / x
phenobarbital / Additional drugs with CYP-450 interactions / x
phenobarbitone / Additional drugs with CYP-450 interactions / x
phenytoin / Additional drugs with CYP-450 interactions / x
pimozide / Additional drugs with CYP-450 interactions / x
PIOGLITAZONE / Common drugs in VA / x / x / x / x
piroxicam / Additional drugs with CYP-450 interactions / x
POTASSIUM CHLORIDE / Common drugs in VA / x / x / x / x
PRAVASTATIN / Common drugs in VA / x / x / x / x
PRAZOSIN / Common drugs in VA / x / x / x / x
PREDNISONE / Common drugs in VA / x / x / x / x
Probenecid / Additional drugs with renal dosing criteria / x
progesterone / Additional drugs with CYP-450 interactions / x
propafenone / Additional drugs with CYP-450 interactions / x
Propoxyphene / Additional drugs with renal dosing criteria / x
PSEUDOEPHEDRINE / Common drugs in VA / x / x / x / x
PSYLLIUM / Common drugs in VA / x / x / x / x
PYRIDOXINE / Common drugs in VA / x / x / x / x
quinidine / Additional drugs with CYP-450 interactions / x
quinine / Additional drugs with CYP-450 interactions / x
RABEPRAZOLE / Common drugs in VA / x / x / x / x
RANITIDINE / Common drugs in VA / x / x / x / x
repaglinide / Additional drugs with CYP-450 interactions / x
rifabutin / Additional drugs with CYP-450 interactions / x
rifampin / Additional drugs with CYP-450 interactions / x
riluzole / Additional drugs with CYP-450 interactions / x
Rimantadine / Additional drugs with renal dosing criteria / x
risperidone / Additional drugs with CYP-450 interactions / x
ritonavir / Additional drugs with CYP-450 interactions / x
ROSIGLITAZONE / Common drugs in VA / x / x / x / x
ROSUVASTATIN / Common drugs in VA / x / x / x / x
SALSALATE / Common drugs in VA / x / x / x / x
saquinavir / Additional drugs with CYP-450 interactions / x
secobarbital / Additional drugs with CYP-450 interactions / x
selegiline / Additional drugs with drug-drug interactions / x
SENNOSIDES / Common drugs in VA / x / x / x / x
SERTRALINE / Common drugs in VA / x / x / x / x
sevoflurane / Additional drugs with CYP-450 interactions / x
SILDENAFIL / Common drugs in VA / x / x / x / x
SIMETHICONE / Common drugs in VA / x / x / x / x
SIMVASTATIN / Common drugs in VA / x / x / x / x
SPIRONOLACTONE / Common drugs in VA / x / x / x / x
St. John's wort / Additional drugs with CYP-450 interactions / x
sulfamethoxazole / Additional drugs with CYP-450 interactions / x
SULFAMETHOXAZOLE-TRIMETOHPRIM / Common drugs in VA / x / x / x / x
tacrine / Additional drugs with CYP-450 interactions / x
tacrolimus / Additional drugs with CYP-450 interactions / x
tamoxifen / Additional drugs with CYP-450 interactions / x
TAMSULOSIN / Common drugs in VA / x / x / x / x
telithromycin / Additional drugs with CYP-450 interactions / x
TEMAZEPAM / Common drugs in VA / x / x / x / x
TERAZOSIN / Common drugs in VA / x / x / x / x
theophylline / Additional drugs with CYP-450 interactions / x
THEOPHYLLINE SR / Common drugs in VA / x / x / x / x
THIAMINE / Common drugs in VA / x / x / x / x
thioridazine / Additional drugs with CYP-450 interactions / x
thiotepa / Additional drugs with CYP-450 interactions / x
TICLOPIDINE / Common drugs in VA / x / x / x / x
timolol / Additional drugs with CYP-450 interactions / x
tizanidine / Additional drugs with CYP-450 interactions / x
tolbutamide / Additional drugs with CYP-450 interactions / x
torsemide / Additional drugs with CYP-450 interactions / x
TRAMADOL / Common drugs in VA / x / x / x / x
tranylcypromine / Additional drugs with drug-drug interactions / x
TRAZODONE / Common drugs in VA / x / x / x / x / x
triamterene / Additional drugs with CYP-450 interactions / x
triazolam / Additional drugs with CYP-450 interactions / x
troglitazone / Additional drugs with CYP-450 interactions / x
troleandomycin / Additional drugs with CYP-450 interactions / x
trovafloxacin / Additional drugs with CYP-450 interactions / x
Valacyclovir / Additional drugs with renal dosing criteria / x
VALSARTAN / Common drugs in VA / x / x / x / x
VARDENAFIL / Common drugs in VA / x / x / x / x
venlafaxine / Additional drugs with CYP-450 interactions / x
verapamil / Additional drugs with CYP-450 interactions / x
vincristine / Additional drugs with CYP-450 interactions / x
VITAMIN D / Common drugs in VA / x / x / x / x
VITAMIN E / Common drugs in VA / x / x / x / x
WARFARIN / Common drugs in VA / x / x / x / x
zileuton / Additional drugs with CYP-450 interactions / x
zolmitriptan / Additional drugs with CYP-450 interactions / x

“Common drugs in VA” = 132 of the most commonly used drugs in VA; “Additional drugs with CYP-450 interactions “ = additional drugs with clinically important CYP-450 interactions identified from “Additional drugs with renal dosing criteria” = additional drugs with renal dosing criteria in older adults identified in Hanlon et al; “Additional drugs with drug-drug interactions” = additional drugs with clinically relevant drug-drug interactions identified from Malone et al.

Hanlon JT, Aspinall SL, SemlaTP, et al. Consensus guidelines for oral dosing of primarily renally cleared medications in older adults. J Am Geriatr Soc. Feb 2009;57(2):335-340.

Malone DC, Abarca J, Hansten PD, et al. Identification of serious drug-drug interactions: results of the partnership to prevent drug-drug interactions. J Am Pharm Assoc (2003). Mar-Apr 2004;44(2):142-151.