Medicines & Prescribing
Medicines, explained clearly
Referenced, plain-language guides to 107 common drug classes — how they work, key safety points and monitoring, cross-linked to our clinical calculators.
Education and reference only. No doses are given here. Always check the SmPC, the BNF and local guidance before prescribing.
Men's health 5-alpha-reductase inhibitors Shrink an enlarged prostate over months — a different approach from alpha-blockers. Cardiovascular ACE inhibitors First-line drugs for hypertension, heart failure and kidney protection — names ending in "-pril". Addiction medicine Alcohol-dependence drugs Medicines that help people stay off alcohol after stopping — alongside psychological support. Bone & metabolism Allopurinol The first-line drug to prevent gout attacks by lowering uric acid. Men's health Alpha-blockers (prostate) Relax the prostate and bladder neck to ease urinary symptoms in men. Anti-infective Aminoglycosides Powerful antibiotics for serious Gram-negative infection that need careful, weight- and renal-based dosing and level monitoring. Gastrointestinal Aminosalicylates The mainstay for mild-to-moderate ulcerative colitis — to treat flares and maintain remission. Cardiovascular Amiodarone A powerful rhythm-control drug reserved for difficult arrhythmias — effective but with a long list of organ effects. Gastrointestinal Antacids and alginates Fast, on-demand relief for heartburn and indigestion — often the sensible first step. Rheumatology Anti-TNF biologics Injectable "biologic" drugs that calm severe inflammatory disease by blocking a key inflammatory signal. Neurology Anticholinesterase dementia drugs Help symptoms in Alzheimer's and some other dementias — modest but worthwhile benefit. Haematology Anticoagulant reversal agents Specialist agents used to reverse blood-thinners in serious bleeding or before urgent surgery. Gastrointestinal Antidiarrhoeals Short-term relief for acute diarrhoea — with clear limits on when not to use them. Gastrointestinal Antiemetics Drugs that prevent and treat nausea and vomiting — the right choice depends on the cause. Allergy Antihistamines Relieve allergy symptoms; newer ones cause little drowsiness. Cardiovascular Antiplatelet drugs Reduce clot formation in arterial disease — used after heart attack, stroke and stenting. Mental health Antipsychotics Drugs for psychosis, bipolar disorder and other conditions — balanced against movement and metabolic side-effects. Endocrine / Diabetes Antithyroid drugs Bring an overactive thyroid under control in hyperthyroidism. Anti-infective Antiviral drugs (herpes) Treat cold sores, genital herpes and shingles — most effective when started early. Cardiovascular ARBs Blood-pressure and heart/kidney protective drugs, often used when an ACE inhibitor causes cough — names ending in "-sartan". Oncology Aromatase inhibitors Hormone treatment for breast cancer after the menopause — with attention to bone and joints. Rheumatology Azathioprine A long-term immune-suppressing drug for autoimmune disease and transplantation. Anti-infective Azole antifungals Common antifungal drugs — effective, but major sources of drug interactions. Mental health Benzodiazepines and Z-drugs Calming and sleep medicines for short-term use — effective but habit-forming. Cardiovascular Beta-blockers Slow the heart and reduce its workload — used in angina, heart failure, arrhythmia and more; names ending in "-olol". Cardiovascular Bile-acid sequestrants Older cholesterol-lowering drugs, also useful for bile-acid diarrhoea and itch. Bone & metabolism Bisphosphonates First-line drugs to strengthen bone and reduce fracture risk in osteoporosis. Women's health Bladder antimuscarinics Calm an overactive bladder and urgency — weighed against anticholinergic side-effects. Cardiovascular Calcium-channel blockers Widely used for blood pressure and angina; some also slow the heart rate. Mental health Clozapine The most effective drug for treatment-resistant schizophrenia — used within a strict monitoring scheme. Bone & metabolism Colchicine An anti-inflammatory for gout flares and some other conditions — effective but easy to overdose. Women's health Combined hormonal contraception Oestrogen-plus-progestogen contraception — highly effective, with specific eligibility checks. Bone & metabolism Denosumab A twice-yearly injection for osteoporosis — with a crucial "don't miss or stop without cover" rule. Cardiovascular Digoxin An old but useful drug for atrial fibrillation and heart failure — with a narrow safety margin. Cardiovascular / Haematology DOACs Modern anticoagulants for AF and venous thrombosis that usually need no routine INR monitoring. Neurology Dopamine agonists Parkinson's and restless-legs drugs that mimic dopamine — effective, but with distinctive behavioural risks. Endocrine / Diabetes DPP-4 inhibitors Well-tolerated oral diabetes drugs that rarely cause hypos — names ending in "-gliptin". Dermatology Emollients The everyday foundation of eczema and dry-skin care — used generously and often. Haematology Erythropoiesis-stimulating agents Boost red-cell production in anaemia of kidney disease and some other settings. Cardiovascular Ezetimibe A cholesterol-lowering tablet used alongside or instead of a statin. Cardiovascular Fibrates Mainly lower triglycerides — used in specific lipid problems rather than as routine cholesterol drugs. Cardiovascular Flecainide Restores and maintains normal rhythm in selected arrhythmias — only in structurally normal hearts. Anti-infective Fluoroquinolones Broad-spectrum antibiotics now restricted to specific situations because of serious side-effects. Neurology Gabapentinoids Used for nerve pain, some seizures and anxiety — now controlled drugs because of misuse risk. Ophthalmology Glaucoma eye drops Daily drops that lower eye pressure to protect sight in glaucoma. Endocrine / Diabetes GLP-1 receptor agonists Injectable (and some oral) diabetes drugs that lower glucose and support weight loss. Gastrointestinal H2-receptor antagonists Acid-reducing drugs for heartburn and ulcers — a gentler step than PPIs in some situations. Haematology Heparins Injectable blood-thinners used to prevent and treat clots, including in hospital and pregnancy. Rheumatology Hydroxychloroquine A well-tolerated long-term drug for lupus and rheumatoid arthritis. Anti-infective Influenza antivirals Reduce the duration of flu and protect high-risk people — most useful started early. Respiratory Inhaled corticosteroids The "preventer" inhalers that control airway inflammation in asthma. Endocrine / Diabetes Insulin The essential hormone replacement for type 1 diabetes and advanced type 2 diabetes. Cardiovascular Ivabradine Slows the heart in heart failure and angina without lowering blood pressure — only in normal (sinus) rhythm. Neurology Lamotrigine Used for epilepsy and bipolar depression — effective and, unlike valproate, generally suitable in pregnancy. Gastrointestinal Laxatives Different types for different problems — chosen by cause and stool consistency. Respiratory Leukotriene receptor antagonists A tablet add-on for asthma, useful where allergy or exercise is prominent. Neurology Levetiracetam A widely used, easy-to-start epilepsy drug — main watch-point is mood and behaviour. Neurology Levodopa The most effective treatment for Parkinson's disease symptoms. Endocrine Levothyroxine Replaces thyroid hormone in an underactive thyroid — titrated to blood tests. Mental health Lithium A highly effective mood stabiliser for bipolar disorder — with a narrow safety margin that demands monitoring. Respiratory Long-acting bronchodilators Maintenance inhalers that keep airways open in asthma and COPD. Cardiovascular / Renal Loop diuretics Strong "water tablets" used mainly to relieve fluid overload in heart failure. Anti-infective Macrolide antibiotics Common antibiotics for respiratory and other infections, and an option in penicillin allergy. Neurology Melatonin A hormone used for short-term insomnia and certain sleep problems — gentler than traditional sleeping pills. Neurology Memantine Used in moderate-to-severe Alzheimer's disease — a different mechanism from the cholinergic drugs. Women's health Menopausal hormone therapy (HRT) Relieves menopausal symptoms and protects bone — with an individualised benefit–risk discussion. Endocrine / Diabetes Metformin First-line oral medicine for type 2 diabetes that does not usually cause hypoglycaemia. Rheumatology Methotrexate A weekly immune-modifying drug for rheumatoid arthritis, psoriasis and more — safe when the rules are followed. Anti-infective Metronidazole Treats anaerobic bacterial and certain parasitic infections — with a strict no-alcohol rule. Mental health Mirtazapine An antidepressant that often helps sleep and appetite — useful when those are a problem. Allergy Nasal corticosteroids The most effective treatment for persistent allergic rhinitis and nasal congestion. Cardiovascular Nitrates Relieve and prevent angina by widening blood vessels. Pain & inflammation NSAIDs Common anti-inflammatory painkillers with important gastrointestinal, renal and cardiovascular cautions. Pain Opioid analgesics Strong painkillers for acute, cancer and palliative pain — effective but with dependence and overdose risks. Addiction medicine Opioid substitution therapy Stabilising treatment for opioid dependence — reducing harm, illicit use and overdose deaths. Haematology Oral iron First-line treatment for iron-deficiency anaemia — effective but often poorly tolerated. Gastrointestinal Orlistat Blocks fat absorption to support weight loss alongside diet and activity. Cardiovascular PCSK9 inhibitors Powerful injectable drugs that lower LDL cholesterol when statins are not enough. Anti-infective Penicillins A large, widely used antibiotic family — first-line for many common infections. Cardiovascular / Renal Phosphate binders Lower phosphate levels in advanced kidney disease — taken with food to work. Women's health Progestogen-only contraception Oestrogen-free contraception suitable when combined methods are not — including while breastfeeding. Gastrointestinal Proton pump inhibitors Powerful acid-suppressing drugs for reflux and ulcers — names ending in "-prazole". Bone & metabolism Raloxifene A bone-protecting drug for post-menopausal osteoporosis, with a breast-risk benefit but a clot caution. Cardiovascular Sacubitril/valsartan A combination heart-failure drug that improves outcomes beyond an ACE inhibitor or ARB alone. Endocrine / Cardiovascular SGLT2 inhibitors Diabetes drugs that also protect the heart and kidneys — names ending in "-flozin". Respiratory Short-acting bronchodilators The "reliever" inhalers that quickly open the airways in asthma and COPD. Neurology Skeletal muscle relaxants Reduce muscle spasticity and spasm in conditions such as MS and spinal injury. Respiratory Smoking-cessation aids Medicines that roughly double the chance of quitting smoking when combined with support. Mental health SNRIs Antidepressants that also help certain nerve-pain and anxiety conditions. Neurology Sodium valproate An effective antiepileptic and mood stabiliser with critical pregnancy-related safety rules. Cardiovascular / Renal Spironolactone A potassium-sparing diuretic used in heart failure, resistant hypertension and fluid from liver disease. Mental health SSRIs First-line antidepressants also used for anxiety disorders. Cardiovascular Statins Lower cholesterol and cardiovascular risk — names ending in "-statin". Endocrine / Diabetes Sulfonylureas Oral diabetes drugs that lower glucose quickly but can cause hypos and weight gain. Endocrine / Immunology Systemic corticosteroids Powerful anti-inflammatory and immunosuppressant drugs — effective but with important short- and long-term effects. Oncology Tamoxifen A long-term hormone treatment that reduces the risk of breast-cancer recurrence. Anti-infective Terbinafine The usual oral treatment for fungal nail and stubborn skin infections. Bone & metabolism Teriparatide A daily injection that builds new bone in severe osteoporosis — used for a limited period. Men's health Testosterone replacement Replaces testosterone in men with confirmed deficiency — not a general tonic. Respiratory Theophylline An older oral bronchodilator now used selectively because of its narrow safety margin. Cardiovascular Thiazide diuretics Mild "water tablets" used mainly for blood pressure. Dermatology Topical corticosteroids Anti-inflammatory creams for eczema and other skin conditions — matched in strength to the site and severity. Mental health Tricyclic antidepressants Older antidepressants now used more often at low dose for nerve pain and other conditions. Neurology Triptans Targeted treatments that stop a migraine attack once it has started. Anti-infective UTI antibiotics First-line antibiotics for urine infections — choice shaped by kidney function and pregnancy. Bone & metabolism Vitamin D Corrects deficiency and supports bone health — widely used and generally very safe. Cardiovascular / Haematology Warfarin A long-established anticoagulant that needs regular INR monitoring and dose adjustment.
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Answers
Frequently asked questions
Are these a substitute for the BNF or SmPC?
No. These are plain-language class overviews for orientation and education. They contain no doses. For prescribing, always use the current Summary of Product Characteristics (SmPC), the BNF and your local formulary.
Why don't the guides show doses?
Doses depend on the exact product, indication, age, weight and kidney function, and they change. Publishing fixed doses would be unsafe and would duplicate licensed sources. We link you to the authoritative monograph instead, and provide calculators (renal function, body weight, risk scores) that support dosing decisions.
How current is this and who writes it?
The guides are original educational content written and reviewed under clinical direction, with a last-reviewed date in the page data. They are reviewed periodically; the authoritative sources we link to are updated continuously.
Will you add individual medicines and an interactions checker?
We are expanding coverage. A full medicines A–Z built on the open NHS dictionary of medicines and devices (dm+d) and a properly licensed interactions resource are on the roadmap — built on permitted data, never scraped.
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