Keytruda

Keytruda is given as an intravenous (IV) injection through a vein over 30 minutes (infusion) every 3 or 6 weeks. The dose of Keytruda you will be given depends on many factors, including your weight, your general health or other health problems, and the type of cancer being treated. Your doctor will work out your dose and schedule.

During the infusion

Most people have few side effects during the infusion. On rare occasions Keytruda can cause a reaction while it's being given. This usually happens within 30 minutes to 2 hours after starting the first infusion. You may experience fever, chills, flushing, skin rash, itching, dizziness headache or have trouble breathing.

Tell the nurse immediately if any of these symptoms occur. This reaction is usually mild and can sometimes be controlled by giving Keytruda more slowly. 

Before starting Keytruda, tell your doctor about any other medicines you are taking including prescription, over-the-counter, vitamins, or herbal remedies.

Tell your doctor if you're pregnant or may be pregnant before starting Keytruda. Keytruda isn't recommended for use during pregnancy. You should avoid becoming pregnant while you are on Keytruda. Use effective birth control during treatment and for at least 4 months after your final dose of Keytruda. Ask your doctor when you may safely become pregnant after therapy. 

Tell your doctor if you're breastfeeding or plan to breastfeed. It's advised not to breastfeed during treatment with Keytruda and for 4 months after your final dose.

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

Vaccinations

• Since Keytruda affects your immune system, you're at increased risk of infection. It's strongly advised that you're up-to-date with the annual flu vaccination and the COVID-19 vaccinations. These are non-live vaccines and they're safe to have while you are receiving immune checkpoint inhibitor treatment.
• Live vaccines such as MMR (measles, mumps and rubella) and varicella (chickenpox vaccine) should NOT be given while you are receiving immune checkpoint inhibitor treatment and for 6 months after treatment has stopped.

Treatment delays

There may be times when your treatment is delayed. This can happen:

• if your doctor thinks you may have severe side effects
• if you get severe side effects
• if your blood counts are affected
• if you're finding it hard to cope with the treatment.

Your doctor will tell you if you need any delays to your treatment and the reason why.

Like all medicines, Keytruda can cause side effects, although not everyone gets them. Because Keytruda affects the immune system, it may cause immune cells to attack healthy cells, triggering a variety of side effects.

You may experience side effects at any time during your treatment or even months after treatment has finished. Some side effects go away within a few days or weeks and some may be longer lasting. 

Note: To monitor your side effects, you will need regular reviews and blood tests to check your liver, kidneys and blood before you start treatment and regularly while you are receiving treatment.