Active Ingredients A to Z

Abacavir Abacavir is an antiretroviral used with other HIV medicines to lower the amount of virus in the blood. Before the first dose, you need a blood test for the HLA-B*5701 gene, since carriers can develop a severe, sometimes fatal hypersensitivity reaction and must never take it. 2 medicines View → Abacavir Abiraterone Abiraterone blocks androgen production to treat prostate cancer that no longer responds to standard hormone therapy. It must always be taken with a corticosteroid, since skipping it can cause dangerously high blood pressure and low potassium. 1 medicine View → Abiraterone Acamprosate Acamprosate helps people who have stopped drinking alcohol maintain abstinence by easing the brain-chemical imbalance left behind by long-term use. It is cleared by the kidneys and should not be used in severe kidney impairment. 1 medicine View → Acamprosate Acarbose Acarbose slows carbohydrate digestion to blunt the rise in blood sugar after meals in type 2 diabetes. If it is combined with insulin or a sulfonylurea and hypoglycemia occurs, it must be treated with glucose rather than ordinary table sugar. 1 medicine View → Acarbose Aceclofenac Aceclofenac is an anti-inflammatory painkiller (NSAID) used for arthritis and other musculoskeletal pain. Like all NSAIDs, it carries a well-established risk of heart attack, stroke, and serious stomach bleeding. 1 medicine View → Aceclofenac Acetazolamide Acetazolamide is a carbonic anhydrase inhibitor used to lower eye pressure in glaucoma, prevent altitude sickness, and manage certain seizures and fluid retention. It is a sulfonamide medicine and must be avoided by anyone with a genuine sulfa-drug allergy. 1 medicine View → Acetazolamide Aciclovir Aciclovir is an antiviral that treats cold sores, genital herpes and shingles by blocking viral DNA replication. It is cleared by the kidneys, so you need good hydration and a lower dose if your kidney function is reduced. 1 medicine View → Aciclovir Acitretin Acitretin is an oral retinoid for severe psoriasis that lingers in the body long after stopping, so pregnancy must be avoided for three years after the last dose and alcohol must be avoided throughout treatment. 1 medicine View → Acitretin Adapalene Adapalene is a topical retinoid applied to the skin to treat acne by keeping pores clear and reducing new blemishes. It increases skin sensitivity to sunlight, so daily sunscreen is essential while you use it. 1 medicine View → Adapalene Albendazole Albendazole is an antiparasitic used to treat intestinal worm infections and tissue infections such as hydatid disease. It is teratogenic in animal studies and should be avoided in pregnancy, especially the first trimester. 1 medicine View → Albendazole Alendronic Acid Alendronic acid is a bisphosphonate that slows bone loss to treat and prevent osteoporosis. It must be taken with a full glass of plain water while staying upright for 30 to 60 minutes, to avoid injuring the oesophagus. 1 medicine View → Alendronic Acid Alfacalcidol Alfacalcidol is a ready-activated form of vitamin D that raises calcium levels and strengthens bone, and because it works without needing the kidneys, blood calcium must be checked regularly to avoid dangerous overdose. 2 medicines View → Alfacalcidol Alfuzosin Alfuzosin is an alpha-blocker that relaxes the prostate and bladder neck to ease urination in men with an enlarged prostate, and it can cause a sharp drop in blood pressure, especially after the first dose. 1 medicine View → Alfuzosin Allopurinol Allopurinol lowers uric acid to prevent gout attacks and kidney stones, and in rare cases it triggers a severe, potentially fatal skin reaction, so any new rash means stopping the drug and seeking care immediately. 1 medicine View → Allopurinol Amantadine Amantadine treats Parkinson's disease symptoms and certain drug-induced movement problems, and stopping it suddenly can cause a dangerous withdrawal reaction with high fever, rigidity and confusion. 1 medicine View → Amantadine Ambrisentan Ambrisentan widens the blood vessels in the lungs to treat pulmonary arterial hypertension, and it must never be used in pregnancy because it causes severe birth defects. 1 medicine View → Ambrisentan Amiloride Amiloride is a potassium-sparing diuretic that removes excess fluid without lowering potassium, and combining it with potassium supplements, ACE inhibitors or similar drugs can push potassium to dangerous, heart-stopping levels. 2 medicines View → Amiloride Amiodarone Amiodarone is a potent anti-arrhythmic used for serious irregular heart rhythms. It requires baseline and regular thyroid, liver, lung and eye checks, since it can damage these organs silently over time. 1 medicine View → Amiodarone Amitriptyline Amitriptyline is a tricyclic antidepressant used for depression, nerve pain and migraine prevention. It is highly cardiotoxic in overdose, so only small, carefully counted quantities should be kept at home. 2 medicines View → Amitriptyline Amlodipine Amlodipine relaxes blood vessels to treat high blood pressure and angina, and combining it with high-dose simvastatin raises the risk of serious muscle damage, so simvastatin doses are capped when the two are taken together. 3 medicines View → Amlodipine Amoxicillin Amoxicillin is a penicillin antibiotic used for common bacterial infections such as ear, chest, throat and urinary infections. Anyone with a penicillin allergy must avoid it, and the full course should be finished even after symptoms improve. 5 medicines View → Amoxicillin Ampicillin Ampicillin is a penicillin-type antibiotic for bacterial infections, and it must never be given to anyone with a confirmed penicillin allergy because it can cause a severe, life-threatening allergic reaction. 1 medicine View → Ampicillin Anastrozole Anastrozole is an aromatase inhibitor used to treat hormone-receptor-positive breast cancer in postmenopausal women; it lowers estrogen enough to thin bone, so bone density is checked before and during treatment. 2 medicines View → Anastrozole Apixaban Apixaban is a direct oral anticoagulant (DOAC) that prevents and treats blood clots by blocking factor Xa, and stopping it suddenly sharply raises your risk of a clot. 1 medicine View → Apixaban Aripiprazole Aripiprazole is an atypical antipsychotic used for schizophrenia, bipolar disorder and treatment-resistant depression. As a partial dopamine agonist it causes less weight gain than most antipsychotics, but it can trigger compulsive gambling, eating or spending in some people. 1 medicine View → Aripiprazole Atenolol Atenolol is a cardioselective beta blocker that treats high blood pressure, angina and abnormal heart rhythms, and it must never be stopped abruptly. 1 medicine View → Atenolol Atomoxetine Atomoxetine is a non-stimulant ADHD medicine that carries a warning for increased suicidal thoughts in children and teenagers, especially early in treatment. 1 medicine View → Atomoxetine Atorvastatin Atorvastatin is a statin that lowers LDL cholesterol to reduce the risk of heart attack and stroke. It rarely causes rhabdomyolysis, serious muscle breakdown, which shows up as muscle pain or weakness with dark urine. 1 medicine View → Atorvastatin Avanafil Avanafil is a fast-acting PDE5 inhibitor that improves blood flow to treat erectile dysfunction. It must never be combined with nitrates, which can cause a dangerous drop in blood pressure. 5 medicines View → Avanafil Azathioprine Azathioprine is an immunosuppressant used to prevent transplant rejection and control autoimmune disease; by suppressing the immune system it raises the risk of serious infections and certain cancers, so regular blood monitoring is required. 1 medicine View → Azathioprine Azelaic Acid Azelaic acid is a topical treatment for acne and rosacea whose main risk is local skin irritation, since very little of it is absorbed into the body. 1 medicine View → Azelaic Acid Azelastine Azelastine is an antihistamine nasal spray and eye drop for allergies that can cause drowsiness, so caution is needed with driving and alcohol. 2 medicines View → Azelastine Azilsartan Azilsartan is an ARB for high blood pressure that can seriously harm a developing baby, so it must be stopped as soon as pregnancy is confirmed. 3 medicines View → Azilsartan Azithromycin Azithromycin is a macrolide antibiotic taken as a short course for respiratory, ear, skin and some sexually transmitted infections. It can prolong the heart's electrical rhythm, so it needs caution in people with heart rhythm problems. 2 medicines View → Azithromycin