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An infant reflux suppressant powder that thickens and stabilises stomach contents to reduce regurgitation and gastro-oesophageal reflux in infants and young children.
Magnesium aspartate dihydrate is an oral mineral preparation that supplies magnesium. The selected product is licensed to treat and prevent magnesium deficiency in adults and children aged 2 years and over.
This is a cardioplegic concentrate used during heart surgery. After dilution, it is infused into the coronary arteries during cardiopulmonary bypass to stop the heart beating temporarily and provide a still operating field.
A balanced, isotonic electrolyte solution given into a vein to replace extracellular fluid during illness, injury, surgery or blood-loss shock. It can also help correct mild to moderate metabolic acidosis.
Magnesium citrate is a mineral salt used to replace magnesium when body levels are low. The selected prescription tablet is licensed to treat and prevent magnesium deficiency in people aged 12 years and over.
Magnesium glycerophosphate is an oral mineral supplement used to restore low magnesium levels. It supports normal enzyme activity, nerve signalling and muscle function.
Magnesium hydroxide is a magnesium salt that acts as both an antacid and a laxative. It is used for short-term relief of indigestion-related symptoms and occasional constipation.
Magnesium sulfate heptahydrate is available as hospital injections or infusions and as Epsom Salts crystals. It replaces magnesium and helps control or prevent seizures associated with severe pre-eclampsia and eclampsia; crystals also have licensed oral and external uses.
Mannitol is an osmotic agent. It may be given by infusion in hospital to increase urine flow or reduce pressure in the brain or eye; inhaled mannitol is used under supervision to test airway sensitivity.
Maraviroc is an antiretroviral that blocks the CCR5 receptor used by some HIV-1 strains to enter cells. It is used with other antiretrovirals for treatment-experienced people whose HIV has been confirmed as CCR5-tropic; it does not cure HIV.
Maribavir is a direct-acting antiviral used for adults with cytomegalovirus (CMV) infection or disease after a stem-cell or solid-organ transplant. Its licensed role is for CMV that has not responded to one or more specified antiviral treatments, whether or not resistance is confirmed.
Mavacamten is a cardiac myosin inhibitor for adults with symptomatic obstructive hypertrophic cardiomyopathy. It reduces excessive heart-muscle contraction and obstruction to blood leaving the heart. Treatment requires specialist supervision, genetic testing and echocardiographic monitoring.
A combined live attenuated vaccine that helps protect against measles, mumps and rubella. In current practice, it is used particularly for eligible older children and adults needing catch-up protection, while younger children are routinely offered MMRV.
This live vaccine contains weakened measles, mumps and rubella viruses and prompts the immune system to make protective antibodies. In current NHS practice, MMR is mainly used for eligible people needing protection outside the routine childhood MMRV programme.
Mebendazole is a benzimidazole anthelmintic used for certain intestinal worm infections. Selected UK products treat threadworm, while selected prescription products are also licensed for roundworm, whipworm and hookworm infections.
Mebeverine hydrochloride is an antispasmodic that acts directly on bowel muscle. It is used mainly to relieve abdominal cramps, pain and related symptoms of irritable bowel syndrome (IBS).
Mecasermin is a recombinant form of human insulin-like growth factor-1 (IGF-1). Under specialist supervision, it is used for growth failure in children and adolescents with confirmed severe primary IGF-1 deficiency who produce sufficient growth hormone.
An intravenous lipid emulsion used as part of parenteral nutrition. It supplies energy and essential omega-6 and omega-3 fatty acids when nutrition by mouth or through the gut is impossible, inadequate or unsuitable.
This is an intravenous lipid emulsion used as part of parenteral nutrition when nutritional needs cannot be met adequately through the gut. It supplies calories and essential fatty acids directly into the bloodstream and is usually combined with other nutrients.
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.