Chemo Experts, the easiest way to learn about cancer treatment
Find a Treatment:
Cancer Types

Treatment Name: Pembrolizumab (Keytruda®)

Pembrolizumab (Keytruda®) is an Immunotherapy Regimen for Lung Cancer, Non-Small Cell Lung Cancer (NSCLC)

How does pembrolizumab work?
Pembrolizumab is designed to block the signals that tumor cells use to suppress the immune system and prevent the immune system from attacking lung cancer cells.

Goals of therapy:
Pembrolizumab is given to decrease symptoms from non-small-cell lung cancer (NSCLC) and to slow its spread to other parts of the body. Pembrolizumab is not commonly given with the goal of cure.


Create your own Treatment Tracker

  • Pembrolizumab intravenous infusion (I.V.) over 30 minutes on Day 1

Estimated total infusion time for this treatment:

  • Up to two hours for Day 1 of each Cycle
  • Infusion times are based on clinical studies, but may vary depending on doctor preference or patient tolerability. Pre-medications and intravenous (I.V.) fluids, such as hydration, may add more time

Pembrolizumab is usually given in an outpatient infusion center, allowing the person to go home afterwards.

Pembrolizumab is repeated every 3 or 6 weeks. This is known as one Cycle. Each cycle may be repeated until the drug no longer works, unacceptable side effects occur, or up to 24 months if the cancer has not spread.

Click here for the common starting dose.

Questions to Ask Your...

A better understanding of your treatments will allow you to ask more questions of your healthcare team. We then hope that with the answers, you will get better results and have greater satisfaction with your care. Because we know it's not always easy to know what questions to ask, we've tried to make it easy for you!

Choose any healthcare provider below to see common questions that you may want to ask of this person. Then, either print each list to bring to your clinic visits, or copy the questions and send them as a message to your healthcare team through your electronic medical record.

Side Effects

In clinical studies, the most commonly reported side effects with pembrolizumab are shown here. Side effects sometimes have percentage ranges [example: 14 – 19% have fatigue] because they differed between clinical studies:

  • Fatigue (14 - 19%)
  • Decreased appetite (11 - 14%)
  • Itching (11%)
  • Rash (9 - 10%)
  • Joint pain (9%)
  • Nausea (8 - 11%)
  • Diarrhea (7 - 8%)
  • Decreased thyroid function (7 - 8%)
  • Weakness (5 - 6%)
  • Lung injury (4 - 5%)
  • Increased thyroid function (4%)
  • Mouth sores (4%)
  • Shortness of breath (4%)
  • Fever (4%)
  • Weight loss (4%)
  • Dry skin (4%)
  • Anemia [low red blood cells] (3 - 4%)
  • Infusion-related reaction (3%)
  • Vomiting (3%)
  • Muscle pain (3%)
  • Cough (2%)
  • Chills (2%)
  • Constipation (2%)

Approximately 10% of patients discontinue pembrolizumab due to unacceptable side effects.

Side effect videos Side Effect Videos
Fatigue Fatigue PainPainAnemiaAnemiaNausea and VomitingNausea and VomitingDiarrheaDiarrheaConstipationConstipationBleedingBleeding


How often is monitoring needed?
Labs (blood tests) may be checked before treatment and periodically during treatment. Labs often include: Complete Blood Count (CBC), Comprehensive Metabolic Panel (CMP), TSH (thyroid stimulating hormone), plus any others your doctor may order.

How often is imaging needed?
Imaging may be checked before treatment then approximately every 9 weeks during treatment. Imaging may include: magnetic resonance imaging (MRI), computerized tomography (CT) scans, or positron emission tomography (PET) scans.

How might blood test results/imaging affect treatment?
Depending upon the results, your doctor may advise to continue pembrolizumab as planned, delay therapy, switch therapy, or stop treatment.

ChemoExperts Tips

  • Serious immune reactions may occur. The most common organs affected are the lungs, intestines, liver, thyroid, kidneys, and pituitary gland, but may affect others as well. If immune reactions occur, corticosteroids may be given and pembrolizumab treatment may need to be interrupted or discontinued
  • A pharmacist should ALWAYS review your medication list to ensure that drug interactions are prevented or managed appropriately
  • Clinical trials may exist for non-small cell lung cancer. Ask your doctor if any studies are currently enrolling in your area. If not, go to to search for other centers offering study medications

Patient Assistance & Co-payment Coverage

Patients under the age of 65 years, or those with private insurance plans:
If you have insurance and are looking for patient assistance or copay assistance for Pembrolizumab (Keytruda®), we have provided links that may help.

Visit our Patient Assistance page and click the links to various patient assistance programs for help paying for Pembrolizumab (Keytruda®). Depending upon your income, they may be able to help cover the cost of:

  • Pembrolizumab

For Branded medications (may be available for generic medications too), check with the manufacturer to determine if a co-pay card is offered and if it could reduce your monthly copay.

  • If you are uninsured, check with the manufacturer to determine if you are eligible to receive medication at no cost.

Medicare and Medicaid patients (Patients 65 years or older):
The clinic providing treatment will likely pre-authorize medications and immune therapies such as Pembrolizumab (Keytruda®) and are the best source to help you understand drug cost.

  • Ask to speak with a patient assistance technician or financial counselor at the clinic or hospital administering this therapy.

Emotional Wellness

What is Emotional Wellness?
Emotional wellness is having a positive outlook balanced with a realistic understanding of current life events. This requires both an awareness and acceptance of your emotions. It is with this knowledge that you can develop a plan to take the necessary actions to positively impact your life.

Emotional wellness uses an ongoing process to continually reflect on the stressors of life in a constructive manner to move forward and create happiness.

Because emotional wellness is deeply connected with physical, social, and spiritual wellness, pursuing it often becomes particularly difficult in times of major illness. Despite this difficulty, working toward emotional wellness has been connected to improved treatment outcomes and a higher likelihood of achieving goals of therapy.

Learn more about pursuing emotional wellness while receiving treatment with Pembrolizumab (Keytruda®)

Individual Drug Label Information

Pembrolizumab (Keytruda®)

  • Pembrolizumab is an intravenous (I.V.) infusion commonly infused over 30 minutes 
  • Reactions may occur during an infusion. The infusion may need to stop if this occurs 
  • Dose adjustments may need to be made due to kidney or liver problems 
  • Inflammation in the lung can occur. This is known as pneumonitis. Treatment with pembrolizumab may have to be permanently discontinued if pneumonitis is severe 
  • Severe or life-threatening reactions have occurred and may affect the lung, large intestine, liver, skin, nerves, pancreas or certain glands such as the thyroid or pituitary gland. If severe immune-mediated side effects are experienced, pembrolizumab therapy should be stopped and high-dose steroids should be started  
  • A severe reaction in the intestine (colon) known as “colitis”, may present as diarrhea, abdominal cramping, mucus or red blood in the stool, and may cause a fever. Seek a doctor immediately if any of these symptoms occur. The doctor will evaluate whether it could be infection, whether it is severe enough to advise hospitalization, or whether it can be managed at home with either loperamide (Imodium®) or corticosteroids 
  • Inflammation in the liver can occur. This is known as hepatitis. Treatment with pembrolizumab may have to be permanently discontinued if hepatitis is severe. If moderate or severe, high-dose corticosteroids (such as prednisone 1 to 2 mg/kg or equivalent) are recommended until liver enzymes return to normal, at which time the steroid dose may be slowly decreased over time as tolerated  
  • Fatigue, headache, difficulty thinking, uncontrolled bowel movements, low blood pressure, dizziness, swelling, or muscle aches, may suggest pembrolizumab-induced inflammation of the adrenal, thyroid, or pituitary gland  
  • May cause fetal harm, avoid this drug during pregnancy and breastfeeding. Females of child-bearing potential should take a pregnancy test before starting pembrolizumab and use effective contraceptive during therapy and for at least 30 days after the last dose 
General Pembrolizumab (Keytruda) Side Effects  
  • Fatigue 
  • Itching 
  • Rash 
  • Constipation 
  • Diarrhea 
  • Nausea 
  • Decreased Appetite 
  • Shortness of breath 
  • Cough 
  • Click on the pembrolizumab (Keytruda) package insert below for reported side effects and possible drug interactions

Side Effect Videos
Nausea and VomitingNausea and VomitingDiarrheaDiarrheaHair LossHair LossFatigue Fatigue BleedingBleedingConstipationConstipationPainPainAnemiaAnemia

See DailyMed package insert.

Share this page:


1) Garon EB, Rizvi NA, Hui R, et al. Pembrolizumab for the treatment of non–small-cell lung cancer. N Engl J Med. 2015;372:2018-2028.

2) Herbst RS, Baas P, Kim DW, et al. Pembrolizumab versus docetaxel for previously treated, PD-L1-positive, advanced non-small-cell lung cancer (KEYNOTE-010): a randomised controlled trial. Lancet. 2016;387:1540–1550.

Created: April 26, 2016 Updated: October 3, 2018

What is Lung Cancer, Non-Small Cell Lung Cancer (NSCLC)?

What is Non-Small Cell Lung Cancer?
A disease of the tissue found in the lung.  Non-small cell lung cancer (NSCLC) is the most common type of lung cancer. Known causes include smoking and exposure to environmental toxins.  The stage of NSCLC can vary at diagnosis and throughout treatment.  Stages include stage I, II, III, and IV.  The effectiveness of the treatment may depend upon the stage at diagnosis.

NOTE: Treatment Options listed below are not all-inclusive. Other treatments may be available. ChemoExperts provides drug information and does not recommend any one treatment over another. Only your Doctor can choose which therapy is appropriate for you.

What does Cure mean?

The word “cure” means there are no cancer cells left in the body and cancer will never come back. Depending on the cancer type and stage, this may be the true goal of therapy. However, it is very difficult to prove all cancer cells are gone. Even though images, like X-rays and MRI’s, and blood tests may not show any signs of cancer, there can be a small amount of cancer cells still left in the body. Because of this, doctors use the word “remission” is used more often. This means there are no signs or symptoms of cancer. Patients in remission are followed closely for any signs of cancer returning. Sometimes, more chemotherapy may be given while in remission to prevent the cancer from coming back.

Doctors usually do not consider a patient “cured” until the chance of cancer returning is extremely low. If cancer does return, it usually happens within 5 years of having a remission. Because of this, doctors do not consider a patient cured unless the cancer has not come back within 5 years of remission. The five-year cutoff does not apply to all cancers.

Common Starting Doses

  • Pembrolizumab 200 mg intravenous (I.V.) infusion over 30 minutes on Day 1 every 3 weeks


  • Pembrolizumab 400 mg intravenous (I.V.) infusion over 30 minutes on Day 1 every 6 weeks

What is a CBC?

A Complete Blood Count (CBC) is a frequently ordered blood test that tells clinicians the status of your: 1) White blood cell count, 2) Hemoglobin, and 3) Platelet count at the time the test was taken.

Common uses:
1) White blood cell count (WBC): is used to determine infection risk, or response to chemotherapy. Certain chemotherapy agents may harm our good infection-fighting cells. Sometimes chemotherapy may need to be delayed to allow these cells to recover.

2) Hemoglobin: is used to determine if someone is anemic. Anytime the hemoglobin is below 12 g/dL, the person is said to be anemic. Red blood cell transfusions, and sometimes iron can be given to restore the hemoglobin level, but anemia treatment should always aim at treating the underlying cause or condition.

3) Platelet count: is used to determine if the risk of bleeding is increased or if a platelet transfusion is required to prevent bleeding. Certain medications that increase bleeding risk, such as: aspirin, certain chemotherapy agents, and blood thinners, may need to be stopped temporarily until the platelet count is within a safe range.

What is a CMP?

A Comprehensive Metabolic Panel (CMP) is a frequently ordered blood test that tells clinicians the status of your: 1) Electrolytes & Acid/Base status2) Kidney function, 3) Liver function, 4) Blood sugar, and 5) Calcium at the time the test was taken. It is commonly used to monitor liver and kidney function when beginning new medications such as chemotherapy. A total of 14 tests are run simultaneously and are shown below.

Electrolytes & Acid/Base status:
1) Sodium, 2) Potassium, 3) Carbon dioxide, 4) Chloride

Kidney Function:
5) BUN (blood urea nitrogen), 6) Serum creatinine (Scr)

Liver Function:
7) AST, 8) ALT, 9) Total bilirubin, 10) Alk Phos, 11) Albumin, 12) Total protein

Blood sugar:
13) Serum glucose

14) Serum calcium