- Obstar
- Oceral
- Octalbin
- Octelmin
- Ocufen
- Oddibil
- Odontovac
- Oflox
- Ofticor
- Ogastro
- Oilatum
- Olbetam
- Olcadil
- Omega-3
- Omep
- Omepramed
- Omeprasec
- Omeprotec
- Omnic 0,4
- Omnipaque
- Omniscan
- Oncovin
- Ondansetron
- One-a-day 50+
- Oprazon
- Optacilin
- Optalidon
- Opti-clean
- Opti-free
- Opti-soak
- Opti-tears
- Opticrom
- Orageston
- Orap
- Orastina
- Orgalutran
- Orimeten
- Ormigrein
- Ornitargin
- Orofungin
- Oroxadin
- Ortoflan
- Os-cal
- Ossopan
- Ossopan 800
- Ostac
- Ostenan
- Osteocalcic
- Osteoplus
- Osteotrat
