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A synthetic progestogen. Tablets are used for selected menstrual or endometriosis problems, or certain hormone-dependent cancers; the depot injection is used for contraception.
Combined hormone replacement therapy containing conjugated oestrogens and medroxyprogesterone acetate. It relieves oestrogen-deficiency symptoms after menopause in people with an intact uterus; the progestogen helps protect the womb lining.
Mefenamic acid is a non-steroidal anti-inflammatory drug (NSAID) that reduces pain, inflammation and fever. Selected products are licensed for arthritis, short-term pain, painful periods and some causes of heavy menstrual bleeding.
Mefloquine hydrochloride is an antimalarial that acts against malaria parasites in red blood cells. Selected tablets are licensed to prevent malaria in suitable travellers and to treat malaria, particularly some infections resistant to other antimalarials.
Megestrol acetate is a synthetic progestogen with anti-oestrogenic activity, used under specialist supervision for certain hormone-dependent cancers, particularly breast cancer.
A water-soluble, iodine-containing contrast agent that makes selected structures more visible during X-ray-based imaging. Selected products support gastrointestinal imaging and abdominal CT, or imaging of vascular and renal systems.
Melatonin is a naturally occurring hormone that regulates the body clock and sleep–wake cycle. Prescription melatonin is used for particular sleep and circadian-rhythm problems; licensed uses vary by product and formulation.
Meloxicam is a prescription non-steroidal anti-inflammatory drug (NSAID) that reduces pain and inflammation. It is mainly used for osteoarthritis flare-ups, rheumatoid arthritis and ankylosing spondylitis.
Melphalan is an alkylating chemotherapy that damages DNA and limits the multiplication of susceptible cells. Its oral tablet is used under specialist supervision for selected cancers and polycythaemia vera.
Melphalan hydrochloride is an alkylating chemotherapy that damages DNA and prevents susceptible cells from multiplying. The selected injectable product is used for several cancers, including multiple myeloma, and may form part of treatment associated with stem-cell transplantation.
Memantine hydrochloride is a prescription anti-dementia treatment licensed for adults with moderate to severe Alzheimer’s disease. It may support cognition, everyday function and overall symptoms, but it does not cure Alzheimer’s disease or prevent all progression.
Menadiol sodium diphosphate is a synthetic, water-soluble vitamin K analogue that helps the body make clotting factors. It is used for bleeding associated with low prothrombin or factor VII, particularly with obstructive jaundice around surgery.
A non-live conjugate vaccine that helps prevent invasive infection, including meningitis and sepsis, caused by meningococcal groups A, C, W135 and Y. It does not protect against every cause of meningitis.
A non-live vaccine that helps prevent invasive disease caused by meningococcal group B bacteria, including meningitis and bloodstream infection. Protection is not complete.
This is a non-live vaccine containing recombinant proteins and an outer-membrane component from meningococcal group B bacteria. It helps prevent invasive MenB disease, including meningitis and sepsis, but does not protect against every MenB strain or every cause of these illnesses.
This is a non-live conjugate vaccine that trains the immune system to recognise meningococcal groups A, C, W-135 and Y. It helps prevent invasive disease such as meningitis and sepsis caused by these groups, but does not protect against every cause of meningitis.
Menotrophin is a gonadotrophin containing follicle-stimulating and luteinising hormone activity. It is used under specialist supervision to stimulate ovarian follicles or sperm production in specific causes of infertility.
Mepolizumab is a specialist monoclonal antibody that reduces inflammation driven by eosinophils, a type of white blood cell. It is used as an add-on treatment for selected severe eosinophilic conditions when existing treatment does not provide adequate control.
Mepyramine maleate is a topical antihistamine used to relieve local skin irritation after insect bites, insect stings and nettle stings. It can reduce itching and has local pain-relieving activity.
Mercaptamine bitartrate supplies cysteamine, a cystine-depleting treatment for proven nephropathic cystinosis. It lowers cystine accumulation within cells and can delay kidney damage, particularly when started early.
Mercaptamine hydrochloride provides cysteamine in eye-drop form. It is used in cystinosis to reduce cystine crystals in the cornea, which can cause light sensitivity, discomfort and impaired vision.
Mercaptopurine is a cytotoxic antimetabolite that interferes with purine metabolism and limits new-cell production. The selected tablet is used under specialist supervision for acute lymphoblastic and acute promyelocytic leukaemia. Specialists also use it without a licence for some inflammatory diseases, including inflammatory bowel disease.
Mercaptopurine monohydrate is a cytotoxic chemotherapy and purine antimetabolite. The selected oral suspension is licensed for acute lymphoblastic leukaemia (ALL) in adults and children; specialists sometimes use it outside its licence for inflammatory bowel disease.
Meropenem trihydrate provides meropenem, a broad-spectrum carbapenem antibiotic. It is given into a vein for serious bacterial infections, usually in hospital or through a supervised outpatient intravenous antibiotic service. It does not treat viral infections.
This is an intravenous combination antibiotic containing the carbapenem meropenem and the beta-lactamase inhibitor vaborbactam. It treats certain serious infections in adults, including infections caused by Gram-negative bacteria when treatment options are limited.
Mesalazine is an aminosalicylate that acts mainly on inflamed bowel tissue. It is used to treat active ulcerative colitis and help maintain remission; some products have more specific licensed roles.
Mesna is used alongside ifosfamide or cyclophosphamide when these treatments could damage the bladder. It makes harmful urinary breakdown products less reactive but does not treat cancer or replace urine monitoring and hydration.
Mestranol with norethisterone is a combined hormonal contraceptive containing an oestrogen and a progestogen. It is used to prevent pregnancy. Norinyl-1 is listed as discontinued on eMC.
Metaraminol tartrate is a sympathomimetic vasopressor that narrows blood vessels and raises blood pressure. In hospital, it is used for acute hypotension caused by loss of blood-vessel tone, including during spinal anaesthesia, alongside other appropriate measures.
This fixed-combination tablet contains metformin, a biguanide, and pioglitazone, a thiazolidinedione. It is licensed as second-line treatment for adults with type 2 diabetes, particularly those who are overweight, when maximum tolerated metformin treatment has not provided sufficient glucose control.
Combines a biguanide with a DPP-4 inhibitor to lower blood glucose in adults with type 2 diabetes, alongside diet and exercise.
Methadone hydrochloride is a long-acting opioid used mainly in supervised treatment for opioid dependence to reduce withdrawal symptoms and cravings. Selected products are also licensed for moderate to severe pain under specialist care.
Methenamine hippurate is a prescription urinary antibacterial that becomes active in acidic urine. It is usually used to help prevent recurrent urinary tract infections after an acute infection has been treated, with additional licensed roles involving catheters and urinary procedures.
Methocarbamol is a prescription-only, centrally acting muscle relaxant used in adults to relieve painful muscle tension, particularly in the lower back.
Methotrexate is a folate antagonist with immunosuppressive and cytotoxic effects. Specialists use it for inflammatory diseases and selected cancers; formulation and schedule depend on the indication.
Methotrexate disodium supplies methotrexate, a folate-antagonist antimetabolite with immunosuppressive and cytotoxic effects. Selected oral products are used for severe inflammatory conditions and specific cancers under specialist supervision.
Methotrexate is an antifolate antimetabolite that suppresses immune and inflammatory activity. The selected tablet is licensed for severe rheumatoid arthritis, severe psoriasis and certain cancers, usually under specialist supervision.
Methoxsalen is a photosensitising psoralen used during extracorporeal photopheresis. It is added to separated white blood cells, activated by UVA light and returned with the blood to help relieve skin manifestations of advanced cutaneous T-cell lymphoma when other treatments have not worked.
Methoxy polyethylene glycol-epoetin beta is an erythropoiesis-stimulating agent that acts like the kidney hormone erythropoietin. It treats symptomatic anaemia caused by chronic kidney disease by helping bone marrow produce more red blood cells.
Methoxyflurane is a volatile, non-opioid inhaled analgesic used under trained supervision for emergency relief of moderate to severe trauma-related pain in conscious patients aged 6 years and older.
Methyl aminolevulinate hydrochloride is a prescription photosensitising cream used in photodynamic therapy. After application to selected abnormal skin lesions, controlled light activates it to damage target cells.
Methyl salicylate is a topical salicylate that increases blood flow in the skin. In Surgical Spirit BP, it is part of a highly alcoholic skin solution licensed to harden foot skin and help prevent bed sores. It is for external use only and must not be used on broken skin.
Methyldopa is a centrally acting antihypertensive that lowers blood pressure by reducing nerve signals that tighten blood vessels. The selected product is licensed for moderate to severe hypertension and may be used during pregnancy under medical supervision.
Methylnaltrexone bromide is a peripherally acting opioid-receptor antagonist used to treat constipation caused by opioid painkillers. In the UK, the selected product is licensed for adults when laxatives have not worked well enough.
Methylphenidate hydrochloride is a central nervous system stimulant used mainly to manage attention deficit hyperactivity disorder (ADHD). It can improve attention and reduce impulsive or hyperactive behaviour as part of a wider treatment programme.
Methylprednisolone is a prescription corticosteroid that reduces inflammation and suppresses immune activity. Oral tablets are licensed for a wide range of inflammatory, allergic, autoimmune, blood, cancer-related and endocrine conditions.
Methylprednisolone acetate is a long-acting corticosteroid injection that reduces inflammation and immune activity. It may be injected locally into joints, soft tissues or skin lesions, or into a muscle for a systemic effect when oral treatment is unsuitable.
An injectable glucocorticoid that rapidly reduces inflammation and immune activity, generally used in hospital for severe or acute conditions.
Methylthioninium chloride, also called methylene blue, is an antidote given into a vein by a healthcare professional for symptomatic methaemoglobinaemia caused by medicines or chemicals.
Metoclopramide is a prescription antiemetic that reduces nausea and vomiting. It acts in the brain and also promotes movement through the upper digestive tract.
Metolazone is a thiazide-like diuretic that helps the kidneys remove sodium and water. It is used for fluid retention associated with heart or kidney disease and can also treat mild or moderate high blood pressure.
Metoprolol tartrate is a beta blocker that mainly reduces adrenaline-like stimulation of the heart. It is used for cardiovascular conditions and migraine prevention; an intravenous formulation is reserved for monitored hospital treatment.
Metreleptin is a laboratory-made analogue of the hormone leptin. It is used alongside diet to treat metabolic complications caused by leptin deficiency in certain people with generalised or partial lipodystrophy.
Metronidazole is an antibacterial and antiprotozoal treatment. Systemic formulations treat or prevent susceptible anaerobic and protozoal infections, while selected skin formulations reduce rosacea spots and redness.
Metronidazole benzoate is used in this oral suspension to provide metronidazole, an antibacterial and antiprotozoal treatment. It is prescribed for susceptible anaerobic bacterial infections and certain parasitic infections, and may also be used to prevent anaerobic infection around surgery.
Metyrapone is a specialist endocrine treatment that reduces cortisol production. It is used to manage endogenous Cushing’s syndrome and in tests of pituitary–adrenal function.
Mexiletine hydrochloride is an oral sodium-channel blocker. The selected Namuscla product is used to reduce delayed muscle relaxation and stiffness caused by non-dystrophic myotonic disorders.
Mianserin hydrochloride is a tetracyclic antidepressant licensed to relieve symptoms of depressive illness. It alters noradrenergic and serotonergic signalling and can have a marked sedative effect.
Micafungin sodium is an echinocandin antifungal given into a vein in hospital. It treats serious Candida infections and can prevent Candida infection in selected people at high risk when other antifungals are unsuitable.
Miconazole is an imidazole antifungal. Selected oral gels treat superficial fungal infections of the mouth and throat, including oral thrush.