| Macrogol price in United Kingdom | 1 | £271 | — | Compare |
| Macrogol Compound Oral Liquid price in United Kingdom | 1 | £11.49 | — | — |
| Magnesium Hydroxide price in United Kingdom | 1 | £4.52 | — | Compare |
| Malathion price in United Kingdom | 1 | £15.96 | — | — |
| Mannitol price in United Kingdom | 1 | £232 | — | Compare |
| Mebendazole price in United Kingdom | 2 | £1.34 | £0.22 | Compare |
| Mebeverine price in United Kingdom | 3 | £3.06 | £0.031 | Compare |
| Medroxyprogesterone price in United Kingdom | 10 | £1.23 | £0.25 | Compare |
| Mefenamic Acid price in United Kingdom | 3 | £7.22 | £0.26 | Compare |
| Mefloquine price in United Kingdom | 1 | £14.53 | £1.82 | Compare |
| Megestrol price in United Kingdom | 1 | £19.52 | £0.65 | Compare |
| Melatonin price in United Kingdom | 13 | £2.55 | £0.36 | Compare |
| Meloxicam price in United Kingdom | 4 | £0.64 | £0.021 | Compare |
| Memantine price in United Kingdom | 7 | £1.09 | £0.039 | Compare |
| Menadiol price in United Kingdom | 1 | £273 | £2.73 | — |
| Menthol price in United Kingdom | 4 | £4.46 | — | Compare |
| Menthol and Methyl Salicylate price in United Kingdom | 1 | £3.30 | — | Compare |
| Meptazinol price in United Kingdom | 1 | £22.11 | £0.20 | — |
| Mepyramine price in United Kingdom | 1 | £4.19 | — | Compare |
| Mercaptamine price in United Kingdom | 5 | £70.00 | £1.90 | — |
| Mercaptopurine price in United Kingdom | 2 | £13.04 | £0.52 | Compare |
| Mesalazine price in United Kingdom | 22 | £14.81 | £0.22 | Compare |
| Metformin price in United Kingdom | 13 | £0.67 | £0.085 | Compare |
| Metformin and Pioglitazone price in United Kingdom | 1 | £29.18 | — | Compare |
| Metformin and Sitagliptin price in United Kingdom | 1 | £3.51 | — | Compare |
| Metformin and Vildagliptin price in United Kingdom | 2 | £19.09 | — | Compare |
| Methadone price in United Kingdom | 8 | £0.94 | £0.40 | Compare |
| Methenamine Hippurate price in United Kingdom | 1 | £32.21 | £0.54 | Compare |
| Methocarbamol price in United Kingdom | 3 | £3.82 | £0.20 | Compare |
| Methotrexate price in United Kingdom | 39 | £1.49 | £0.54 | Compare |
| Methyldopa price in United Kingdom | 3 | £5.47 | £0.44 | Compare |
| Methylnaltrexone price in United Kingdom | 1 | £147 | — | Compare |
| Methylphenidate price in United Kingdom | 15 | £2.80 | £0.093 | Compare |
| Methylprednisolone price in United Kingdom | 8 | £1.58 | £2.42 | Compare |
| Metoclopramide price in United Kingdom | 4 | £0.74 | £0.026 | Compare |
| Metolazone price in United Kingdom | 1 | £110 | £5.50 | Compare |
| Metoprolol price in United Kingdom | 3 | £1.47 | £0.064 | Compare |
| Metronidazole price in United Kingdom | 10 | £0.96 | £0.046 | Compare |
| Metyrapone price in United Kingdom | 1 | £553 | £5.53 | Compare |
| Mexiletine price in United Kingdom | 2 | £375 | £4.46 | Compare |
| Mianserin price in United Kingdom | 2 | £19.56 | £0.70 | Compare |
| Miconazole price in United Kingdom | 5 | £4.89 | — | Compare |
| Midazolam price in United Kingdom | 13 | £5.28 | — | Compare |
| Midodrine price in United Kingdom | 3 | £7.15 | £0.35 | Compare |
| Minocycline price in United Kingdom | 1 | £20.08 | £0.36 | Compare |
| Minoxidil price in United Kingdom | 6 | £8.88 | £0.51 | Compare |
| Mirabegron price in United Kingdom | 2 | £29.00 | £0.97 | Compare |
| Mirtazapine price in United Kingdom | 7 | £1.12 | £0.040 | Compare |
| Misoprostol price in United Kingdom | 1 | £10.03 | £0.17 | Compare |
| Mitotane price in United Kingdom | 1 | £780 | £7.80 | Compare |
| Ml Eye Drops and Netilmicin price in United Kingdom | 1 | £9.83 | — | — |
| Ml Eye Drops and Tafluprost price in United Kingdom | 1 | £12.20 | — | — |
| Ml Eye Drops and Travoprost price in United Kingdom | 1 | £7.49 | — | — |
| Ml Solution For Injection and Sodium Bicarbonate price in United Kingdom | 3 | £127 | — | — |
| Moclobemide price in United Kingdom | 2 | £9.33 | £0.31 | Compare |
| Modafinil price in United Kingdom | 2 | £2.41 | £0.080 | Compare |
| Mometasone price in United Kingdom | 6 | £2.43 | — | Compare |
| Montelukast price in United Kingdom | 4 | £0.94 | £0.034 | Compare |
| Morphine price in United Kingdom | 32 | £2.88 | £0.095 | Compare |
| Moxifloxacin price in United Kingdom | 2 | £9.80 | £2.20 | Compare |
| Moxonidine price in United Kingdom | 3 | £2.07 | £0.17 | Compare |
| Mupirocin price in United Kingdom | 3 | £4.24 | — | Compare |
| Mycophenolate price in United Kingdom | 5 | £6.06 | £0.81 | Compare |