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Macimorelin acetate is an oral diagnostic agent that stimulates growth hormone release. It is used under specialist supervision to help diagnose growth hormone deficiency in adults; it is not a treatment.
Macitentan is an endothelin receptor antagonist used in specialist care for pulmonary arterial hypertension. It reduces the effects of endothelin, which narrows and remodels blood vessels in the lungs.
An osmotic bowel-cleansing preparation containing macrogol 3350 and electrolytes. It produces watery bowel movements to empty the colon before certain investigations or surgery; it is not the same as routine low-volume macrogol treatment for constipation.
Macrogol 3350 with potassium chloride, sodium chloride and sodium hydrogen carbonate is an osmotic laxative with electrolytes. It softens stools and is used for constipation and faecal impaction. Licensed ages vary by product.
Macrogol 4000 is an osmotic laxative that retains water in the bowel, softening stools and making them easier to pass. It is used for symptomatic treatment of constipation alongside appropriate diet, fluid intake and activity.
Macrogol cetostearyl ether is an emulsifying ingredient in a paraffin-containing skin cream. The selected product is licensed as an emollient and as a diluent for externally applied preparations.
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.
Marstacimab is a monoclonal antibody that helps blood clot by blocking tissue factor pathway inhibitor (TFPI). It prevents or reduces bleeding in eligible people with severe haemophilia A or B without factor inhibitors.
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.
A live attenuated vaccine containing weakened measles, mumps, rubella and varicella-zoster viruses. It stimulates immunity against all four infections and is used in the routine UK childhood immunisation programme.
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.
Metformin hydrochloride is a biguanide medicine that lowers blood glucose without directly stimulating insulin release. It is mainly used with diet and physical activity for type 2 diabetes, alone or with other diabetes medicines.
Mirvetuximab soravtansine is a targeted anticancer treatment combining an antibody with a cell-killing payload. It treats certain FRα-positive ovarian, fallopian tube or primary peritoneal cancers resistant to platinum-based treatment.
A non-replicating live-virus vaccine that trains the immune system to recognise related orthopoxviruses. It is licensed in adults against smallpox, mpox and disease caused by vaccinia virus, and is used according to official recommendations.
Mometasone furoate is a corticosteroid that reduces inflammation. Depending on the formulation, it prevents asthma symptoms, relieves allergic inflammation inside the nose, or treats inflamed, itchy skin and scalp conditions.
Montelukast sodium is an oral leukotriene receptor antagonist used mainly to prevent and control asthma symptoms. It is generally an add-on treatment and does not replace a reliever inhaler during an asthma attack.
Morphine sulfate is a strong opioid painkiller for severe pain. It is available as immediate-release and prolonged-release oral products and as injections used in supervised healthcare settings.
The active component of an updated mRNA COVID-19 vaccine targeting the SARS-CoV-2 Omicron LP.8.1 spike protein. The selected product is licensed for people aged 12 years and over, in accordance with official recommendations.
mRNA-1273.167 is an mRNA vaccine that instructs cells to briefly produce the SARS-CoV-2 JN.1 spike protein, prompting an immune response. It is authorised to prevent COVID-19, but its use depends on current official vaccination recommendations.
Mrna-1273.251 is an mRNA vaccine that trains the immune system to recognise the LP.8.1 SARS-CoV-2 spike protein. It is licensed to prevent COVID-19 in people aged 6 months and older, guided by current official recommendations.