Trastuzumab

Trastuzumab is given as a drip into a vein (intravenous infusion)

• It's usually given once every 3 weeks, but can sometimes be given more often depending on your treatment.
• Your dose of trastuzumab depends on many factors, including your weight and type of cancer. Your doctor will work out your dose.
• The first infusion takes about 90 minutes. After that, each dose will usually take 30 minutes.

During the infusion

Trastuzumab is usually given by a nurse at an outpatient unit. For some people, trastuzumab can cause a reaction (called an infusion reaction) while it's being given so you’ll be carefully monitored during the infusion and for a time afterwards. Reactions are usually more common with your first infusion.

• Before the infusion you may be given medicines, eg, paracetamol and an antihistamine.
• Tell your nurse if you have any of these symptoms during your infusion:
  • fever
  • chills
  • flushing
  • skin rash, itching
  • dizziness, headache
  • trouble breathing.

Note: If these symptoms happen after you’ve left the unit, contact your healthcare team or Healthline on 0800 611 116 immediately and tell them you are taking Herzuma.

Here are some things to know when you're having trastuzumab. Other things may be important as well, so ask your healthcare provider what you should know about.

• Reaction during the infusion: Trastuzumab may cause an infusion-related reaction for up to 24 hours after you've received a dose. It’s important that you tell your doctor or go to the Accident and Emergency at your nearest hospital if you notice any unusual symptoms. See the information about an infusion reaction above. 
• Heart problems: Trastuzumab can sometimes affect the heart. You will have regular tests before, during and after treatment to see how well your heart is working. Tell your doctor if you have a history of heart problems or high blood pressure.
• Increased risk of infections: Trastuzumab weakens your body’s defence (immune) system, so you're more likely to pick up infections. It's important to avoid anyone who has chickenpox or shingles.
• Pregnancy: You should avoid becoming pregnant while you're having trastuzumab and for at least 7 months after stopping treatment. Talk to your healthcare provider about which types of contraception are suitable for you and your partner.
• Vaccines: Some vaccines shouldn't be taken if you are on trastuzumab. Always check with your doctor or pharmacist first. It is safe for you to have the annual flu vaccine.
• Other medicines: Trastuzumab may interact with a few medicines and herbal supplements, so check with your doctor or pharmacist before starting trastuzumab or before starting any new medicines. This includes those you may buy over-the-counter.

Like all medicines, trastuzumab can cause side effects, although not everyone gets them. You may experience side effects at any time during your treatment or even months after treatment has finished. Most of the side effects of trastuzumab are likely to improve after you stop having treatment but some may last longer.

Note: Trastuzumab may also be used with chemotherapy, which can cause other side effects or make these side effects worse.

Note: To monitor your side effects, you'll need monitoring and blood tests to check your heart, liver, kidneys and blood before you start treatment and regularly while you're receiving treatment.