| Term | Definition |
| Caduet | amlodipine/atorvastatin |
| Cafegot | ergotamine/caffeine |
| Calan | verapamil 40,80,120 |
| Campral | acamprosate |
| Capoten | captopril |
| Capozide | captopril/hctz |
| Carafate | sucralfate |
| Carbatrol | carbamazepine 100,200,300 (c) |
| Cardizem LA | diltiazem 120,180,240,300,360,420 (LA) |
| Cardura | doxazosin |
| Carnitor | levocarnitine |
| Cartia XT | diltiazem 120,180,240,300 (XT) |
| Casodex | bicalutamide |
| Cataflam | diclofenac potassium |
| Catapres | clonidine |
| Ceclor | cefaclor |
| Cedax | ceftibuten |
| CeeNU | lomustine |
| Ceftin | cefuroxime axetil |
| Cefzil | cefprozil |
| Celebrex | celecoxib |
| Celexa | citalopram |
| Cellcept | mycophenolate mofetil |
| Cenestin | conjugated estrogens |
| Cesamet | nabilone |
| Chantix | varenicline |
| Chemet | succimer |
| Cialis | tadalafil |
| Cipro | ciprofloxacin |
| Claravis | isotretinoin (cl) |
| Clarinex | desloratidine |
| Cleocin | clindamycin |
| Clinoril | sulindac |
| Clomid | clomiphene |
| Clorpres | chlorthalidone/clonidine |
| Clozaril | clozapine |
| Cognex | tacrine |
| Colazal | balsalazide |
| Colestid | colestipol |
| Combivir | lamivudine/zidovudine |
| Combunox | oxycodone/ibuprofen |
| Compazine | prochlorperazine maleate |
| Comtan | entacapone |
| Concerta | methylphenidate ER |
| Copegus | ribavirin |
| Cordarone | amiodarone |
| Coreg | carvedilol |
| Corgard | nadolol |
| Cortef | hydrocortisone |
| Corzide | nadolol/bendroflumethiazide |
| Coumadin | warfarin |
| Covera-HS | verapamil 180,240 |
| Cozaar | losartan |
| Creon | pancrelipase |
| Crestor | rosuvastatin |
| Crixivin | indinavir |
| Cuprimine | penicillamine |
| Cyklokapron | tranexamic acid |
| Cymbalta | duloxetine |
| Cytomel | liothyronine |
| Cytotec | misoprostol |
| Cytoxan | cyclophosohamide |
| Cardizem CD | diltiazem 120,180,240,300,360 (CD) |