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PlainMedicare

Medicare Part D drugs starting with O

71 drugs start with O; 23 of them are on at least 90% of 2026 Part D formularies. Part D spending was highest for Ozempic in 2024: $13.0 billion, what plans and patients paid at the pharmacy before rebates.

Which drugs start with O?

By name; spending is what plans and patients paid at the pharmacy in 2024 (“no 2024 match”: no row of the CMS spending file can be tied to this product alone)
DrugPlans coveringUsual tierMedicare spending, 2024
Octagam (immunoglobulin g, human)56.1%Tier 5$393 million
Octreotide100%Tier 4$6 million
Ocuflox (ofloxacin)under 0.1%Tier 1$7 thousand
Odactra5%Tier 3$1 million
Odefsey (emtricitabine / rilpivirine / tenofovir alafenamide)100%Tier 5$375 million
Odomzo (sonidegib)100%Tier 5$46 million
Ofev (nintedanib)100%Tier 5$2.1 billion
Ofloxacin100%Tier 2$27 million
Ogsiveo (nirogacestat)100%Tier 5$20 million
Ohtuvayre (ensifentrine)7.4%Tier 5$113 thousand
Ojemda (tovorafenib)100%Tier 5$705 thousand
Ojjaara (momelotinib)100%Tier 5$342 million
Olanzapine100%Tier 2$110 million
Olmesartan medoxomil97.5%Tier 1$69 million
Olopatadine hydrochloride34.3%Tier 4$4 million
Olpruva (sodium phenylbutyrate)0.1%Tier 5$488 thousand
Olumiant (baricitinib)4.2%Tier 5$35 million
Omega-3 acid ethyl esters92.8%Tier 2$65 million
Omeprazole100%Tier 1$367 million
Omeprazole / sodium bicarbonate1.2%Tier 4$122 million
Omnaris (ciclesonide)0.2%Tier 4$858 thousand
Omnitrope (somatropin)43.5%Tier 5$10 million
Omvoh (mirikizumab-mrkz)under 0.1%Tier 2$5 million
Onapgo (apomorphine hydrochloride)2.5%Tier 5no 2024 match
Ondansetron100%Tier 2$142 million
Onexton (benzoyl peroxide / clindamycin phosphate)0.4%Tier 4$63 thousand
Onfi (clobazam)under 0.1%Tier 1$31 million
Ongentys (opicapone)6.1%Tier 4$15 million
Onureg (azacitidine)100%Tier 5$86 million
Onyda (clonidine hydrochloride)0.1%Tier 4no 2024 match
Onzetra (sumatriptan)0.2%Tier 4no 2024 match
Opipza (aripiprazole)100%Tier 5no 2024 match
Opsumit (macitentan)79.8%Tier 5$1.2 billion
Opsynvi (macitentan / tadalafil)14%Tier 5$24 million
Opvee (nalmefene)48.8%Tier 3$7 thousand
Opzelura (ruxolitinib)3.4%Tier 5$106 million
Oracea (doxycycline anhydrous)under 0.1%Tier 1$3 million
Orapred (prednisolone)1.9%Tier 4no 2024 match
Orencia (abatacept)20.7%Tier 5$248 million
Orenitram (treprostinil)37%Tier 4$230 million
Show the other 31 drugs
DrugPlans coveringUsual tierMedicare spending, 2024
Orfadin (nitisinone)9.5%Tier 5$243 thousand
Orgovyx (relugolix)100%Tier 5$484 million
Oriahnn (elagolix / estradiol / norethindrone)1.8%Tier 5$289 thousand
Orilissa (elagolix)6.6%Tier 5$3 million
Orkambi (ivacaftor / lumacaftor)76.1%Tier 5$634 thousand
Orladeyo (berotralstat)2.2%Tier 5$78 million
Orlynvah (probenecid / sulopenem etzadroxil)3.6%Tier 5no 2024 match
Ormalvi (dichlorphenamide)1%Tier 5no 2024 match
Orphenadrine citrate7.5%Tier 2$2 million
Orquidea (norethindrone)94.1%Tier 2no 2024 match
Orserdu (elacestrant)100%Tier 5$259 million
Oseltamivir100%Tier 2$19 million
Osenvelt (denosumab-bmwo)36.2%Tier 5no 2024 match
Osphena (ospemifene)22.1%Tier 3$8 million
Ospomyv (denosumab-dssb)25.1%Tier 4no 2024 match
Otezla (apremilast)57.4%Tier 5$1.0 billion
Otulfi (ustekinumab-aauz)18.6%Tier 3no 2024 match
Ovide (malathion)under 0.1%Tier 1no 2024 match
Oxacillin83.3%Tier 4$2 million
Oxaprozin42.9%Tier 4$1 million
Oxazepam27.6%Tier 4$2 million
Oxcarbazepine100%Tier 3$70 million
Oxervate (cenegermin-bkbj)15.3%Tier 5$715 million
Oxiconazole1.6%Tier 4$7 million
Oxistat (oxiconazole)1%Tier 4$246 thousand
Oxybutynin chloride100%Tier 2$111 million
Oxycodone hydrochloride99.8%Tier 3$134 million
Oxycontin (oxycodone hydrochloride)3.7%Tier 1$338 million
Oxymorphone hydrochloride8%Tier 4$20 million
Oxytrol (oxybutynin)0.2%Tier 4$1 million
Ozempic (semaglutide)99%Tier 3$13.0 billion

Source: CMS Part D formulary file, 2026 second quarter; CMS Medicare Part D Spending by Drug, 2024.

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