How does it work?

Actilyse injection contains the active ingredient alteplase, which is a type of medicine called a tissue-type plasminogen activator, or fibrinolytic. It is used to dissolve abnormal blood clots that have caused a heart attack, stroke or blood clot in the lung (pulmonary embolism).

Blood clots normally only form to stop bleeding that has occurred as a result of injury to the tissues. Sometimes, however, a blood clot can form abnormally within the blood vessels. The clot can then get lodged in a blood vessel, blocking the blood supply to a vital organ such as the heart (causing a heart attack), brain (causing an ischaemic stroke) or lungs (causing a pulmonary embolism).

Blood clots are made of red blood cells and platelets bound together with a substance called fibrin. Once they have fulfilled their normal purpose of stopping bleeding, the body dissolves clots by producing another substance called plasmin. Plasmin breaks down fibrin and allows the clots to break up.

Alteplase works by attaching to the fibrin in abnormal blood clots, such as those in the arteries supplying the heart. It then activates the production of plasmin, which causes the clots to disintegrate. This unblocks the blood vessel and allows blood flow to resume to the affected organ.

Alteplase must be given as soon as possible after the onset of symptoms of a heart attack, pulmonary embolism or ischaemic stroke, to reduce the amount of damage to the affected organ.

Treatment for ischaemic stroke must be started within 3 hours of onset of the stroke symptoms and only after a type of stroke caused by bleeding in the brain (haemorrhagic stroke) has been ruled out.

Alteplase is given by injection or infusion (drip) into a vein to break up the blood clot. You will also be given heparin and aspirin to reduce the risk of further blood clots forming.

What is it used for?

• Heart attack (myocardial infarction)
• Pulmonary embolism
• Ischaemic stroke

Use with caution in

• Elderly people
• Children
• Recent minor trauma, including biopsies, injections into muscles, heart massage (CPR), puncture of major blood vessels
• People at increased risk of bleeding

Not to be used in

• Active or recent severe or dangerous bleeding
• Blood clotting disorders such as haemophilia
• People taking anticoagulant medicines to prevent blood clots, such as warfarin
• History of or suspected bleeding inside the skull (intracranial haemorrhage)
• Suspected bleeding in the brain (subarachnoid haemorrhage)
• History of damage to the brain or spinal cord (eg caused by cancer, aneurysm, brain or spinal surgery)
• People who have had external heart massage (CPR) in the last 10 days
• People who have had puncture of a blood vessel such as the subclavian or jugular vein in the last 10 days
• Women who have given birth in the last 10 days
• Severe, uncontrolled high blood pressure in the arteries (arterial hypertension)
• Bacterial infection of the heart valves and the lining surrounding the heart (bacterial endocarditis)
• Inflammation of sac surrounding the heart (pericarditis)
• Inflammation of pancreas (pancreatitis)
• People who have had a peptic ulcer in the last three months
• Dilated and fragile veins in the lower oesophagus (oesophageal varices), frequently caused by liver cirrhosis
• Arterial aneurysm
• Cancers with increased risk of bleeding
• Severe liver disease such as liver failure, cirrhosis or hepatitis
• People who have had major surgery or significant injury in the last three months.
• When treating a heart attack or pulmonary embolism, this medicine should also not be used in people with a history of stroke.
• When treating ischaemic stroke, this medicine should only be used by specialists in neurology, as there are various other specialist criteria for when the medicine should not be used, including severe strokes, people who had a seizure at the start of the stroke, who have evidence or symptoms of bleeding in the skull or brain, who are diabetic and have a history of stroke, who have had a previous stroke in the last three months, or who have problems with blood sugar levels, platelet counts or high blood pressure.
• This medicine should not be used for treating acute stroke in children under 18 years or adults over 80 years of age.

This medicine should not be used if you are allergic to one or any of its ingredients. Please inform your doctor or pharmacist if you have previously experienced such an allergy.If you feel you have experienced an allergic reaction, stop using this medicine and inform your doctor or pharmacist immediately.

Pregnancy and Breastfeeding

Certain medicines should not be used during pregnancy or breastfeeding. However, other medicines may be safely used in pregnancy or breastfeeding providing the benefits to the mother outweigh the risks to the unborn baby. Always inform your doctor if you are pregnant or planning a pregnancy, before using any medicine.

• This medicine should only be used during pregnancy if the expected benefit to the mother is greater than any possible risk to the foetus. Seek medical advice from your doctor.
• There is no information available regarding the safety of this medicine during breastfeeding. Seek medical advice from your doctor.

Side effects

Medicines and their possible side effects can affect individual people in different ways. The following are some of the side effects that are known to be associated with this medicine. Because a side effect is stated here, it does not mean that all people using this medicine will experience that or any side effect.

• Bleeding
• Nausea and vomiting
• Low blood pressure (hypotension)
• Fever (pyrexia)
• Abnormal heart beats when treating heart attack (arrhythmias)
• An extreme allergic reaction (anaphylaxis)

The side effects listed above may not include all of the side effects reported by the drug's manufacturer.For more information about any other possible risks associated with this medicine, please read the information provided with the medicine or consult your doctor or pharmacist.

How can this medicine affect other medicines?

There is an increased risk of bleeding if any of the following medicines are used before, during, or in the 24 hours after treatment with alteplase:

• antiplatelet medicines, eg aspirin, dipyridamole, clopidogrel
• heparin or low molecular weight heparins such as enoxaparin
• heparinoids, eg danaparoid
• lepirudin or bivalirudin
• abciximab, eptifibatide or tirofiban
• oral anticoagulants, eg warfarin, nicoumalone, phenindione.

There may be an increased risk of allergic reactions to this medicine if it is used in people taking ACE inhibitor medicines.

Other medicines containing the same active ingredient

There are currently no other medicines available in the UK that contain alteplase as the active ingredient.