Medicines Starting with O
Browse canonical medicine guides by name. Page coverage varies, so use the sections and references shown on each guide and confirm personal treatment decisions with a qualified clinician or pharmacist.
These directory links help readers and search engines reach one preferred URL for each medicine.
Browse medicines by letter
All canonical medicines
- Oat Bran
- Obeticholic acid
- Obinutuzumab
- Octreotide
- Ofatumumab
- Ofloxacin
- Olanzapine
- Olaparib
- Olaratumab
- Olatec: Potential approval 2026–2027 if Phase 3 succeeds.
- Olmesartan
- Olodaterol
- Olopatadine
- Omadacycline
- Omalizumab
- Omeprazole
- Ondansetron
- Opicapone
- Opium tincture
- Oregano Oil
- Orfenadrine
- Orforglipron
- Oritavancin
- Orlistat
- Ormeloxifene
- Oseltamivir
- Osimertinib / Osimertinib mesylate
- Ospemifene
- Oxacillin
- Oxaprozin
- Oxazepam
- Oxcarbazepine
- Oxeladin
- Oxybutynin
- Oxycodone
- Oxymetazoline
- Oxytetracycline
- Oxytocin
- Ozanimod