Prime
- Kabbikinase
- Kabolin
- Kadian
- Kalcinate
- Kaletra
- kanamycin
- Kantrex
- kaolin/pectin
- Kaopectate
- Kaopectate Advanced Formula
- Kaopectate II Caplets
- Kaopectate Maximum Strength
- Kaopek
- Kao-Spen
- Kapectolin
- Karacil
- Karidium
- Karigel
- Kariva
- Kayexalate
- Keflex
- Keftab
- Keletra
- Kenacort
- Kenaject
- Kenalog
- Kenonel
- Keppra
- Kerlone
- Ketalar
- ketamine
- ketoconazole
- ketoconazole (systemic)
- ketoprofen
- ketorolac
- kew
- kew tree
- K-Exit
- Key-Pred
- Kidrolase
- Kineret
- Klamath weed
- Klean-Prep
- Klonopin
- knitbone
- Koate-DVI
- Koffex
- Kogenate
- Kogenate FS
- Kondremul
- Kondremul Plain
- Konsyl
- Konsyl Fiber
- Korean ginseng
- K-Pek
- K-Phos
- K-Phos Original
- Kritalose
- Ku-Zyme HP
- Kytril