| Term | Definition |
| Dalmane | flurazepam |
| Dantrium | dantrolene |
| Daraprim | pyrimethamine |
| Darvocet A500 | propoxyphene napsylate/APAP 100/500 |
| Darvocet N100 | propoxyphene napsylate/APAP 100/650 |
| Darvocet N50 | propoxyphene napsylate/APAP 50/325 |
| Darvon | propoxyphene HCl 65mg |
| Darvon-N | propoxyphene napsylate 100 |
| Daypro | oxaprozin |
| DDAVP | desmopressin |
| Decadron | dexamethasone |
| Declomycin | demeclocycline |
| Deconamine SR | chlorpheniramine/pseudoephedrine |
| Demadex | torsemide |
| Demerol | meperidine |
| Depakene | valproic acid |
| Depakote | divalproex sodium |
| Detrol | tolterodine |
| Dexedrine | dextroamphetamine |
| DiaBeta | glyburide |
| Diabinese | chlorpropamide |
| Diamox | acetazolamide |
| Dibenzyline | phenoxybenzamine |
| Didrex | benzphetamine |
| Didronel | etidronate |
| Diflucan | fluconazole |
| Dilacor XR | diltiazem 120,180,240 (Dilacor XR) |
| Dilantin | phenytoin |
| Dilatrate-SR | isosorbide dinitrate |
| Dilaudid | hydromorphone |
| Dilt-CD | diltiazem 120,180,240,300 (Dilt-CD) |
| Diltia XT | diltiazem 120,180,240 (Diltia XT) |
| Diovan | valsartan |
| Diovan HCT | valsartan/HCTZ |
| Dipentum | olsalazine |
| Diprivan | propofol |
| Ditropan | oxybutynin |
| Dolobid | diflunisal |
| Dolophine | methadone |
| Donnatal | atropine/hyoscamine/phenobarbital/scopolamine |
| Doryx | doxycycline |
| Dostinex | cabergoline |
| Drisdol | ergocalciferol |
| Droxia | hydroxyurea |
| Duetact | pioglitazone/glimepiride |
| Duradrin | dichloralphenazone/isometheptene/APAP |
| Duricef | cefadroxil |
| Dyazide | triamterene/HCTZ |
| Dynacirc CR | isradipine |
| Dyrenium | triamterene |