Medicare Part D drugs starting with M
124 drugs start with M; 65 of them are on at least 90% of 2026 Part D formularies. Part D spending was highest for Mounjaro in 2024: $6.3 billion, what plans and patients paid at the pharmacy before rebates.
Which drugs start with M?
| Drug | Plans covering | Usual tier | Medicare spending, 2024 |
|---|---|---|---|
| M-M-R II (MMR vaccine) | 100% | Tier 1 | $2 million |
| Macrodantin (nitrofurantoin, macrocrystals) | 0.1% | Tier 4 | $5 thousand |
| Magnesium chloride and 4 more ingredients | 75.7% | Tier 4 | no 2024 match |
| Magnesium sulfate | 100% | Tier 4 | no 2024 match |
| Magnesium sulfate / potassium sulfate / sodium sulfate | 98.6% | Tier 4 | no 2024 match |
| Malarone (atovaquone / proguanil hydrochloride) | 0.2% | Tier 1 | $3 thousand |
| Malathion | 99% | Tier 4 | $352 thousand |
| Maraviroc | 100% | Tier 5 | $19 million |
| Marlissa (ethinyl estradiol / levonorgestrel) | 96.1% | Tier 2 | $27 thousand |
| Marplan (isocarboxazid) | 100% | Tier 4 | $349 thousand |
| Matulane (procarbazine) | 100% | Tier 5 | $2 million |
| Matzim (diltiazem hydrochloride) | 58.4% | Tier 2 | $4 million |
| Mavenclad (cladribine) | 3.4% | Tier 5 | $178 million |
| Mavyret (glecaprevir / pibrentasvir) | 66.3% | Tier 5 | $165 million |
| Maxalt (rizatriptan) | under 0.1% | Tier 1 | $1 million |
| Maxidex (dexamethasone) | 0.7% | Tier 4 | $99 thousand |
| Maxitrol (dexamethasone / neomycin / polymyxin b) | under 0.1% | Tier 1 | $24 thousand |
| Mayzent (siponimod) | 8.2% | Tier 3 | $76 million |
| Meclizine hydrochloride | 99.5% | Tier 2 | $25 million |
| Meclofenamate | 3% | Tier 2 | $258 thousand |
| Medrol (methylprednisolone) | 7.3% | Tier 3 | $10 thousand |
| Medroxyprogesterone acetate | 100% | Tier 1 | $9 million |
| Mefenamic acid | 4.4% | Tier 4 | $72 thousand |
| Mefloquine hydrochloride | 100% | Tier 2 | $402 thousand |
| Megestrol acetate | 100% | Tier 3 | $28 million |
| Mekinist (trametinib) | 100% | Tier 5 | $207 million |
| Mektovi (binimetinib) | 100% | Tier 5 | $96 million |
| Meleya (norethindrone) | 94.2% | Tier 2 | no 2024 match |
| Meloxicam | 100% | Tier 1 | $68 million |
| Memantine hydrochloride | 100% | Tier 2 | $231 million |
| Menostar (estradiol) | 0.5% | Tier 4 | $605 thousand |
| MenQuadfi (meningococcal ACWY vaccine) | 100% | Tier 1 | $2 million |
| Menveo (meningococcal ACWY vaccine) | 100% | Tier 1 | no 2024 match |
| Meperidine hydrochloride | 2% | Tier 2 | $1 million |
| Meprobamate | 4% | Tier 1 | $1 million |
| Mepron (atovaquone) | 0.1% | Tier 5 | $251 thousand |
| Mercaptopurine | 100% | Tier 3 | $5 million |
| Merilog (insulin aspart-szjj) | 6.7% | Tier 3 | no 2024 match |
| Meropenem | 100% | Tier 3 | $17 million |
| Mesalamine | 100% | Tier 4 | $268 million |
Show the other 84 drugs
| Drug | Plans covering | Usual tier | Medicare spending, 2024 |
|---|---|---|---|
| Mesna | 100% | Tier 5 | $5 thousand |
| Mesnex (mesna) | 2.1% | Tier 5 | $690 thousand |
| Mestinon (pyridostigmine bromide) | under 0.1% | Tier 1 | $8 million |
| Metaxalone | 3.8% | Tier 2 | $8 million |
| Metformin hydrochloride | 100% | Tier 1 | $290 million |
| Metformin hydrochloride / pioglitazone | 91.3% | Tier 1 | $4 million |
| Metformin hydrochloride / saxagliptin | 7.1% | Tier 3 | $6 million |
| Metformin hydrochloride / sitagliptin | 0.6% | Tier 1 | $101 thousand |
| Methadone hydrochloride | 99.5% | Tier 3 | $11 million |
| Methamphetamine hydrochloride | 1.1% | Tier 4 | $207 thousand |
| Methazolamide | 96.4% | Tier 4 | $10 million |
| Methenamine hippurate | 98.9% | Tier 3 | $61 million |
| Methimazole | 100% | Tier 1 | $11 million |
| Methitest (methyltestosterone) | 2.8% | Tier 5 | $357 thousand |
| Methocarbamol | 72.1% | Tier 2 | $36 million |
| Methotrexate | 100% | Tier 2 | $58 million |
| Methoxsalen | 59.8% | Tier 5 | $541 thousand |
| Methscopolamine bromide | 40.7% | Tier 4 | $665 thousand |
| Methsuximide | 100% | Tier 4 | $383 thousand |
| Methyldopa | 25% | Tier 2 | no 2024 match |
| Methylphenidate | 1.3% | Tier 4 | $355 thousand |
| Methylphenidate hydrochloride | 100% | Tier 2 | $36 million |
| Methylprednisolone | 100% | Tier 2 | $42 million |
| Methyltestosterone | 20.3% | Tier 5 | $309 thousand |
| Metoclopramide | 100% | Tier 1 | $8 million |
| Metolazone | 99.3% | Tier 2 | $14 million |
| Metoprolol succinate | 100% | Tier 1 | $456 million |
| Metoprolol tartrate | 100% | Tier 1 | $107 million |
| MetroCream (metronidazole) | under 0.1% | Tier 1 | no 2024 match |
| Metronidazole | 100% | Tier 1 | $56 million |
| Metyrosine | 100% | Tier 5 | $4 million |
| Mexiletine hydrochloride | 52.3% | Tier 2 | $9 million |
| Mibelas 24 Fe Chewable (ethinyl estradiol / norethindrone acetate) | 39.1% | Tier 2 | no 2024 match |
| Micafungin | 96.9% | Tier 4 | $7 million |
| Micardis-HCT (hydrochlorothiazide / telmisartan) | under 0.1% | Tier 1 | no 2024 match |
| Miconazole nitrate | 58.1% | Tier 2 | $137 thousand |
| Microencapsulated potassium chloride | 100% | Tier 2 | no 2024 match |
| Microgestin (ethinyl estradiol / norethindrone acetate) | 95.3% | Tier 2 | $83 thousand |
| Microgestin Fe (ethinyl estradiol / norethindrone acetate) | 95.9% | Tier 2 | $41 thousand |
| Midodrine hydrochloride | 100% | Tier 2 | $104 million |
| Miebo (perfluorohexyloctane) | 64.8% | Tier 3 | $116 million |
| Mifepristone | 100% | Tier 5 | $7 million |
| Migergot (caffeine / ergotamine tartrate) | 8% | Tier 5 | $2 million |
| Miglitol | 39.8% | Tier 4 | $495 thousand |
| Miglustat | 32.5% | Tier 5 | $5 million |
| Mili (ethinyl estradiol / norgestimate) | 95.9% | Tier 2 | $144 thousand |
| Mimvey (estradiol / norethindrone acetate) | 72.3% | Tier 4 | $362 thousand |
| Minivelle (estradiol) | 0.3% | Tier 4 | $1 million |
| Minocycline | 100% | Tier 2 | $9 million |
| Minoxidil | 100% | Tier 2 | $9 million |
| Minzoya (ethinyl estradiol / levonorgestrel) | 5.7% | Tier 2 | no 2024 match |
| Miplyffa (arimoclomol) | 5.8% | Tier 5 | $2 million |
| Mirabegron | 20.3% | Tier 3 | $134 million |
| Mirena (levonorgestrel) | 24% | Tier 4 | $758 thousand |
| Mirtazapine | 100% | Tier 2 | $158 million |
| Misoprostol | 100% | Tier 3 | $4 million |
| Mitigare (colchicine) | 4.3% | Tier 3 | $14 million |
| Modafinil | 99.9% | Tier 3 | $27 million |
| Modeyso (dordaviprone) | 100% | Tier 5 | no 2024 match |
| Moexipril hydrochloride | 94.9% | Tier 1 | $924 thousand |
| Molindone hydrochloride | 100% | Tier 4 | $372 thousand |
| Mometasone furoate | 100% | Tier 2 | $44 million |
| Montelukast | 100% | Tier 1 | $136 million |
| Morphine sulfate | 100% | Tier 3 | $75 million |
| Motpoly (lacosamide) | 1.3% | Tier 4 | $394 thousand |
| Mounjaro (tirzepatide) | 97% | Tier 3 | $6.3 billion |
| Movantik (naloxegol) | 95.3% | Tier 3 | $153 million |
| MoviPrep (ascorbic acid and 5 more ingredients) | under 0.1% | Tier 1 | $48 thousand |
| Moxifloxacin | 100% | Tier 2 | $28 million |
| Mresvia (RSV vaccine) | 100% | Tier 1 | $10 million |
| Mulpleta (lusutrombopag) | 2.2% | Tier 5 | $205 thousand |
| Multaq (dronedarone) | 92.7% | Tier 3 | $415 million |
| Mupirocin | 100% | Tier 2 | $39 million |
| Myalept (metreleptin) | 2.1% | Tier 5 | $15 million |
| Mycapssa (octreotide) | 0.3% | Tier 5 | $10 million |
| Mycophenolate mofetil | 100% | Tier 2 | $63 million |
| Mycophenolic acid | 100% | Tier 4 | $17 million |
| Myfembree (estradiol / norethindrone acetate / relugolix) | 2.8% | Tier 5 | $2 million |
| Myfortic (mycophenolic acid) | 2.1% | Tier 4 | $1 million |
| Myhibbin (mycophenolate mofetil) | 16% | Tier 5 | $13 thousand |
| Myqorzo (aficamten) | 0.2% | Tier 4 | no 2024 match |
| Myrbetriq (mirabegron) | 79.9% | Tier 3 | $2.3 billion |
| Mysoline (primidone) | under 0.1% | Tier 1 | $13 million |
| Mytesi (crofelemer) | 2.9% | Tier 5 | $8 million |
Source: CMS Part D formulary file, 2026 second quarter; CMS Medicare Part D Spending by Drug, 2024.
What else should you check?
- Every drug, by letterAnd the 20 that cost Medicare most
- Stand-alone drug plans for 2027Premiums and deductibles
- Part D in 2027What changes for drug plans