Actilyse

Indications

Alteplase is a clot-dissolving medicine used in hospital emergencies. It is used to treat acute ischaemic stroke (a stroke caused by a blood clot in the brain) when it can be started within a few hours of symptoms beginning, usually up to 4.5 hours, after a brain scan has ruled out bleeding. It is also used for certain heart attacks and for large, life-threatening clots in the lungs (massive pulmonary embolism). A low-strength form is used to clear blocked central venous catheters.

How It Works

Alteplase is a man-made copy of a natural enzyme called tissue plasminogen activator. It attaches to the clot and converts plasminogen into plasmin, an enzyme that breaks down fibrin, the mesh that holds a blood clot together. This dissolves the clot and can restore blood flow to the brain, heart or lungs, limiting damage if given early enough.

Dosage and Administration

Alteplase is given only in hospital by doctors and nurses, as an injection into a vein followed by a drip (infusion). The dose is calculated by the doctor based on the condition being treated and the patient's body weight. Blood pressure, nerve function and signs of bleeding are monitored closely during and after treatment. For catheter clearance, a small amount is placed into the catheter by trained staff.

Interactions

Medicines that affect blood clotting increase the risk of bleeding, including Heparin, Warfarin and other anticoagulants, and antiplatelet medicines such as Aspirin and Clopidogrel; the doctor decides whether and when these are given. ACE inhibitors such as Enalapril or Ramipril may increase the risk of swelling of the tongue, lips or throat (angioedema). Tell the medical team about all medicines, especially blood thinners.

Contraindications

It must not be used in people with active bleeding, a bleeding disorder, a history of bleeding in the brain, a recent stroke or serious head injury, recent major surgery or trauma, very high blood pressure that cannot be controlled, a brain tumour or aneurysm, severe liver disease, or recent bleeding from the stomach or bowel. The doctor checks a detailed list of conditions before giving it.

Side Effects

The main risk is bleeding. Possible side effects include:

• Bleeding or bruising at injection or catheter sites
• Bleeding from the gums, nose, stomach, bowel or urine
• Bleeding in the brain, which can be serious
• Swelling of the tongue, lips or throat
• Nausea, vomiting, low blood pressure, irregular heartbeat as blood flow returns
• Fever or allergic reactions

Tell the nurse or doctor immediately about sudden severe headache, worsening weakness or confusion, vomiting blood, black stools, swelling of the face or throat, difficulty breathing or any new bleeding during or after treatment.

Pregnancy and Lactation

Experience in pregnancy is limited and it may increase the risk of bleeding for mother and baby. It is used in pregnancy only for life-threatening conditions when the doctor judges the benefit outweighs the risk. It is not known whether it passes into breast milk; the doctor will advise on breastfeeding after treatment.

Precautions and Warnings

Treatment is given in a hospital that can manage bleeding and monitor the patient closely. Injections into muscles and unnecessary needle punctures are avoided. Extra care is taken in older patients, people with recent minor surgery, low platelets, high blood sugar or uncontrolled high blood pressure. Anticoagulant or antiplatelet treatment is usually withheld for a set time after stroke treatment, as decided by the doctor.

Overdose

Too much Alteplase increases the risk of serious bleeding. The medical team will stop the infusion and give supportive treatment, which may include blood products.

Therapeutic Class

Thrombolytic (fibrinolytic) agent; tissue plasminogen activator.

Storage

Hospital medicine: store as directed on the pack, usually below 25°C, protected from light. Use the prepared solution as directed. Keep out of the reach of children.