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Clarithromycin is a prescription macrolide antibiotic that stops susceptible bacteria making proteins needed for growth. It treats selected respiratory, ear, skin and soft-tissue infections and is used with other treatments to eradicate Helicobacter pylori.
Clarithromycin lactobionate is a water-soluble form of clarithromycin used to prepare an intravenous infusion. It is generally used in hospital for susceptible respiratory, throat, sinus, skin or soft-tissue infections requiring intravenous treatment.
Clindamycin hydrochloride is a prescription-only lincosamide antibiotic. Oral capsules are licensed for serious infections caused by susceptible Gram-positive or anaerobic bacteria.
Clindamycin phosphate is converted into clindamycin, a lincosamide antibiotic. Formulations include an injection for serious susceptible infections, skin preparations for acne and a vaginal cream for bacterial vaginosis.
This prescription gel combines a topical antibiotic with a retinoid. It treats acne with blocked pores and inflamed spots.
Clobazam is a benzodiazepine that reduces excessive brain activity. Selected products are licensed as add-on treatment for epilepsy and for symptom relief in severe anxiety. It is not an antipsychotic.
Clobetasol propionate is a very potent corticosteroid applied to the skin or scalp to reduce inflammation, itching and irritation. It is generally reserved for steroid-responsive conditions that have not responded adequately to less potent corticosteroids.
This skin treatment combines a very potent corticosteroid with an antibiotic and an antifungal. It is used for resistant inflammatory skin conditions when secondary bacterial or candidal infection is present, suspected or likely.
Clobetasone butyrate is a moderately potent corticosteroid applied to the skin. It reduces inflammation, itching and irritation in steroid-responsive conditions such as eczema and dermatitis.
This skin cream combines a moderately potent corticosteroid with an antibiotic and an antifungal. It is used for inflamed, itchy skin conditions when bacterial or candidal infection is present, suspected or likely.
Clomethiazole is a short-acting sedative and hypnotic with anticonvulsant effects. UK oral products are licensed for selected symptoms in older people and for alcohol withdrawal under close hospital supervision.
Clomifene citrate is an ovulation stimulant used for certain types of infertility when ovulation is absent or disrupted and other causes have been assessed.
Clomipramine hydrochloride is a prescription-only tricyclic antidepressant for adults. Licensed uses include depressive illness where sedation is helpful, obsessional or phobic states, and additional treatment for cataplexy associated with narcolepsy.
Clonazepam is a benzodiazepine that reduces abnormal electrical activity in the brain. Selected UK products are licensed mainly for epilepsy; licensed ages and seizure types vary by product.
Clonidine hydrochloride is a centrally acting alpha-2 agonist that reduces sympathetic nerve signals. Licensed uses vary by formulation and include migraine prevention, menopausal flushing, hypertension and hospital treatment of hypertensive crises.
Cloral betaine is a hypnotic that converts to chloral hydrate in the body. It is licensed for severe insomnia that disrupts daily life when behavioural measures and other treatments have failed.
An injectable botulinum toxin type A preparation that reduces selected nerve signals to muscles, sweat glands or the bladder. Specialists use it for certain forms of spasm, spasticity, excessive underarm sweating and neurological bladder incontinence.
Clotrimazole is an azole antifungal used locally on the skin or in and around the vagina. Selected UK products treat fungal skin infections, vaginal thrush and external vulval irritation caused by thrush.
This combines two azole antifungals. Oral fluconazole treats Candida systemically, while external clotrimazole treats soreness and itching around affected genital skin. It is intended for previously diagnosed vaginal or penile thrush.
This skin cream combines an antifungal with a mild corticosteroid. It treats certain fungal skin infections when redness, itching or swelling is present.
Clove oil is a dental solution for temporary toothache relief. It acts locally but does not treat the underlying dental problem, so dental assessment remains important.
Clozapine is mainly used when schizophrenia has not responded to other antipsychotics or they have caused severe neurological effects. It is also licensed for psychosis associated with Parkinson’s disease when standard treatment has failed. Specialist supervision and regular blood monitoring are required.
Co-trimoxazole combines trimethoprim and sulfamethoxazole. It treats selected susceptible infections and can prevent Pneumocystis jirovecii pneumonia or toxoplasmosis. Infusion is generally reserved for when oral treatment is unsuitable.
Coal tar extract is a topical treatment that reduces excessive skin-cell turnover and helps relieve scaling and itching. As a medicated shampoo, it is licensed for dandruff, seborrhoeic dermatitis of the scalp and scalp psoriasis. The selected Neutrogena T/Gel product is marked as discontinued on eMC.
Coal tar solution is a topical tar preparation for psoriasis of the skin or scalp. It helps reduce scaling, inflammation and itching by slowing excessive skin-cell production.
A topical ointment combining coal tar, sulfur and salicylic acid. It loosens thick scale, reduces excessive skin hardening and relieves irritation in scaly scalp conditions.
A topical tar preparation used to manage psoriasis by reducing excessive skin-cell production, scaling and itching. Its precise action is not fully understood.
A rinse-off shampoo combining coal tar, salicylic acid and coconut oil. It reduces itching and scale while softening the scalp in conditions including dandruff, seborrhoeic dermatitis, psoriasis and cradle cap.
Cobicistat is a pharmacokinetic enhancer used in combination treatment for HIV-1. It has no direct antiviral activity; it slows the breakdown of certain HIV protease inhibitors.
This fixed combination contains darunavir, an HIV protease inhibitor, and cobicistat, which increases darunavir exposure but has no antiviral activity itself. It is used with other antiretrovirals to treat HIV-1 under specialist care.
A fixed-combination antiretroviral treatment for HIV-1. It controls HIV but does not cure the infection.
A fixed combination of four antiretroviral substances used to control HIV-1 infection. Elvitegravir, emtricitabine and tenofovir alafenamide act against the virus; cobicistat increases elvitegravir exposure.
A fixed-dose combination of three antiretroviral agents and cobicistat, which boosts elvitegravir exposure. It is licensed as a complete treatment for selected adults and adolescents with HIV-1, subject to resistance, kidney and other clinical considerations.
Cobimetinib hemifumarate is a targeted anticancer treatment called a MEK inhibitor. In the UK, it is licensed with vemurafenib for adults with BRAF V600 mutation-positive melanoma that cannot be removed surgically or has spread.
Cocaine hydrochloride is a topical local anaesthetic that also narrows blood vessels. The selected UK product is applied by trained clinicians to accessible mucous membranes before surgery, particularly in the mouth, larynx or nose.
Combines an opioid analgesic with a non-steroidal anti-inflammatory drug (NSAID). Selected products are licensed for acute moderate pain not relieved by paracetamol, ibuprofen or aspirin alone.
Colchicine is an anti-inflammatory treatment used mainly for gout. It treats inflammation during attacks and can help prevent flares when urate-lowering treatment starts, but does not lower uric acid.
Colecalciferol, also called cholecalciferol or vitamin D3, helps the body absorb calcium and phosphate. It prevents or treats vitamin D deficiency and may support osteoporosis treatment when vitamin D is insufficient.
Colesevelam hydrochloride is a bile acid sequestrant that stays in the gut and lowers LDL cholesterol. It is used alongside diet, either alone when a statin is unsuitable or with other cholesterol-lowering treatments.
Colestyramine anhydrous is a bile acid-binding resin that remains in the gut. It lowers cholesterol and relieves certain forms of itching or diarrhoea linked to bile acids.
Colistimethate sodium is converted to the active antibiotic colistin. It is inhaled for chronic Pseudomonas aeruginosa lung infection in cystic fibrosis, while intravenous treatment is reserved for serious Gram-negative infections when options are limited.
Conestat alfa is a recombinant version of human C1 esterase inhibitor, produced in the milk of genetically modified rabbits. It treats acute swelling attacks caused by C1 esterase inhibitor deficiency in hereditary angioedema.
Crizotinib is an oral targeted anticancer treatment that blocks abnormal signalling from ALK, ROS1 and related proteins. In the UK, it is licensed for selected advanced non-small cell lung cancers in adults and certain ALK-positive tumours in children and adolescents.
Crotamiton is a topical antipruritic that relieves itching and skin irritation. It also acts against scabies mites and is licensed for treating scabies.
This topical combination pairs crotamiton’s anti-itch action with the anti-inflammatory and anti-allergic effects of mild corticosteroid hydrocortisone. It is used on small areas of inflamed, itchy skin caused by certain forms of dermatitis, eczema or insect-bite reactions.
Crovalimab is a monoclonal antibody and complement C5 inhibitor used alone to control red blood cell destruction in eligible adults and adolescents with paroxysmal nocturnal haemoglobinuria (PNH).
Cyanocobalamin is a manufactured form of vitamin B12 used to prevent or treat deficiency. It supports healthy red blood-cell formation and nervous-system function.
Cyclizine hydrochloride is a sedating antihistamine with anti-sickness and anticholinergic effects. It can prevent or relieve nausea and vomiting and help vertigo linked to inner-ear disorders.
This combines dipipanone, a strong opioid painkiller, with cyclizine, an anti-sickness antihistamine. It is licensed for moderate to severe pain where morphine may be appropriate, while helping prevent opioid-related nausea and vomiting.
Cyclizine lactate is an injectable antihistamine with anti-sickness and anticholinergic effects. Selected UK products are licensed for adults to prevent or treat nausea and vomiting, particularly when oral treatment cannot be used, and for certain vestibular symptoms.
Cyclopentolate hydrochloride is an antimuscarinic eye drop that widens the pupil and temporarily prevents focusing. It is usually used during eye examinations and may support management of certain inflammatory eye conditions.
Cyclophosphamide is a cytotoxic alkylating agent used for certain blood cancers, solid tumours and selected life-threatening autoimmune diseases. Specialist-led treatment can affect blood cells, fertility, the bladder and other organs.
Cyclophosphamide monohydrate supplies cyclophosphamide, an alkylating cytotoxic treatment that also suppresses immune activity. It is used mainly for cancers; an injectable product is also licensed for certain life-threatening autoimmune diseases.
Cycloserine is an antibiotic used mainly by specialist teams for susceptible tuberculosis when primary treatments have failed. Its UK licence also covers selected acute urinary tract infections after conventional treatment has failed.
Cyproterone acetate is a hormonal anti-androgen that blocks androgen action and reduces androgen production. Selected UK products are used in prostate cancer care and, when other interventions are inappropriate, to control libido in adult men with severe hypersexuality or sexual deviation.
A combined hormonal treatment containing an anti-androgen and an oestrogen. It treats androgen-sensitive moderate to severe acne or excessive hair growth in women of reproductive age when appropriate acne treatments have not worked. Although contraceptive, it should not be used solely for contraception.
Cytarabine is an antimetabolite chemotherapy that disrupts DNA production in rapidly dividing cells. It is mainly used, alone or with other anticancer treatments, for leukaemias and some lymphomas.
This is a liposomal combination chemotherapy containing cytarabine and daunorubicin. In the UK, it is used for adults with newly diagnosed therapy-related acute myeloid leukaemia or acute myeloid leukaemia with myelodysplasia-related changes.