| MOPS | | Amino acids | 1 |
| MOPS Sodium | | Amino acids | 1 |
| MYRISTIC ACID | | Surfactants | 1 |
| Methylphenobarbital | 115-38-8 | Barbiturates | 1 |
| Methylpropan-2-yl)oxy]-18-oxooctadecanoic Acid | 33402-03-8 | | 1 |
| Methylumbelliferone | 532-23-1 | | 1 |
| Metomidate | 35944-74-2 | | 1 |
| Metronidazole benzoate | 13182-89-3 | | 1 |
| Metyrapone | 54-36-4 | Adrenal steroid inhibitors | 1 |
| Mexidole | 127464-43-1 | | 1 |
| Mezlocillin | 51481-65-3 | Cephalosporins | 1 |
| Midodrine Hydrochloride | 3092-17-9 | | 1 |
| Milk thistle | 65666-07-1 | | 1 |
| Mirogabalin Besylate | 843666-40-0 | | 1 |
| Mistletoe | | Herbal remedies | 1 |
| Mitapivat | 1260075-17-9 | Genitourinary Agents | 1 |
| Mitotane | 53-19-0 | Alkylating agents | 1 |
| Mivacurium chloride intermediates | 61349-11-9 | | 1 |
| Molindone | 7416-34-4 | Atypical antipsychotics | 1 |
| Monensin | 796073-69-3 | | 1 |
| Monobasic Potassium Phosphate | 7778-77-0 | | 1 |
| Monomethyl Auristatin F | 745017-94-1 | Antineoplastics | 1 |
| Monosodium citrate | 18996-35-5 | Citrate salts | 1 |
| Moroxydine hydrochloride | 3160-91-6 | Antivirals | 1 |
| Morpholine | 110-91-8 | Solvents | 1 |
| Mosapride citrate | 112885-42-4 | | 1 |
| Motherwort | | Herbal remedies | 1 |
| Moxidectin | 1138245-21-2 | | 1 |
| Mucopolysaccharidase | | Enzyme Replacements/modifiers | 1 |
| Mugwort | | Herbal remedies | 1 |
| Mullein flower | | Herbal remedies | 1 |
| Musk mallow | | Herbal remedies | 1 |
| Mycophenolate Mofetil Hydrochloride | 885101-89-3 | | 1 |
| N –Phenylbenzylamine | 103-32-2 | | 1 |
| N-(2 -Cyanobiphenyl-4-ylmethyl)-L-valine Methyl Ester Hydrochloride | 482577-59-3 | Intermediates | 1 |
| N-Acetyl-D-glucosamine | 7512-17-6 | Dietary supplements | 1 |
| N-Acetyl-L-Glutamate | 1188-37-0 | Amino acids | 1 |
| N-[(S)-(2,3,4,5,6-pentafluorophenoxy)phenoxyphosphinyl]-L-alanine 1-Methylethyl ester | 1911578-98-7 | | 1 |
| mexidol | 127464-43-1 | | 1 |
| n- Octane | 111-65-9 | | 1 |