Active Ingredients A to Z

Every branded generic we stock, organised by active ingredient, so you can find the affordable alternative to any big-name original. The brand changes; the active ingredient does not.

Sacubitril Sacubitril is combined with valsartan, as Entresto, to treat chronic heart failure. It can cause serious swelling of the face or throat (angioedema) and must not be started within 36 hours of stopping an ACE inhibitor. 1 medicine View Sacubitril Salbutamol Salbutamol is a fast-acting bronchodilator used to relieve asthma and COPD symptoms. Needing it more often than usual is a warning sign that your asthma is getting worse and needs urgent medical review. 5 medicines View Salbutamol Salmeterol Salmeterol is a long-acting bronchodilator used to control asthma and COPD. In asthma it must never be used alone: it carries a boxed warning for increased risk of asthma-related death unless combined with an inhaled corticosteroid. 3 medicines View Salmeterol Saxagliptin Saxagliptin is a DPP-4 inhibitor used to lower blood sugar in type 2 diabetes. It has been linked to a higher rate of hospitalization for heart failure, so report new or worsening swelling or breathlessness to your doctor promptly. 1 medicine View Saxagliptin Selegiline Selegiline is a selective MAO-B inhibitor used in Parkinson's disease and depression. At higher doses it loses its selectivity and can cause a dangerous rise in blood pressure with tyramine-rich foods or serotonin syndrome with certain other medicines. 1 medicine View Selegiline Semaglutide Semaglutide is a GLP-1 receptor agonist for type 2 diabetes and weight management, given as a once-weekly injection or a once-daily tablet, carrying a boxed warning for thyroid C-cell tumours in anyone with a personal or family history of medullary thyroid cancer or MEN2. 1 medicine View Semaglutide Sertraline Sertraline is an SSRI antidepressant used for depression, anxiety and related conditions. It carries a boxed warning: it can increase suicidal thoughts in people under 25, especially in the first weeks of treatment. 1 medicine View Sertraline Sildenafil Sildenafil is a PDE5 inhibitor that improves blood flow to treat erectile dysfunction and pulmonary hypertension. It must never be combined with nitrates, which can cause a dangerous drop in blood pressure. 46 medicines View Sildenafil Simvastatin Simvastatin is a statin that lowers LDL cholesterol to reduce the risk of heart attack and stroke. Grapefruit juice and certain heart and antifungal medicines raise its levels and the risk of serious muscle breakdown, so doses are often capped when combined. 1 medicine View Simvastatin Sirolimus Sirolimus is an immunosuppressant used to prevent organ transplant rejection. It increases the risk of serious infections and certain cancers, and requires regular blood-level monitoring because its safe dose range is narrow. 1 medicine View Sirolimus Sitagliptin Sitagliptin is a DPP-4 inhibitor for type 2 diabetes with a low risk of hypoglycemia when used alone, though it carries a rare risk of pancreatitis that needs urgent attention if severe abdominal pain occurs. 2 medicines View Sitagliptin Sofosbuvir Sofosbuvir is a direct-acting antiviral used to treat chronic hepatitis C. Combining it with amiodarone can cause serious, sometimes fatal slowing of the heart rate, and it can reactivate hepatitis B in people previously infected with that virus. 4 medicines View Sofosbuvir Solifenacin Solifenacin is an antimuscarinic that relaxes the bladder to treat overactive bladder. It should not be used if you have urinary retention or uncontrolled narrow-angle glaucoma, since both can become dangerously worse. 1 medicine View Solifenacin Sorafenib Sorafenib is a kinase inhibitor used to treat advanced liver, kidney and thyroid cancers. It commonly causes hand-foot skin reaction, raised blood pressure and bleeding, so regular monitoring is essential during treatment. 1 medicine View Sorafenib Sotalol Sotalol is a beta-blocker with class III antiarrhythmic effects used to control irregular heart rhythms. Because it can prolong the QT interval and trigger a dangerous rhythm, treatment is started in hospital with continuous ECG monitoring. 1 medicine View Sotalol Spironolactone Spironolactone is a potassium-sparing diuretic used for fluid retention, high blood pressure and hormonal conditions. Its main risk is hyperkalaemia (high blood potassium), so blood potassium and kidney function are monitored regularly. 1 medicine View Spironolactone Sulfasalazine Sulfasalazine is an anti-inflammatory used for ulcerative colitis and rheumatoid arthritis. It is contraindicated in sulfa or salicylate allergy, and regular blood counts are needed to catch rare but serious drops in blood cell counts. 1 medicine View Sulfasalazine Sumatriptan Sumatriptan is a triptan that relieves migraine and cluster headache attacks by narrowing blood vessels. It is contraindicated in coronary artery disease, prior stroke, and uncontrolled high blood pressure because of this vessel-narrowing effect. 1 medicine View Sumatriptan