Many medications can cause side effects. A side effect is an unwanted response to a medication when it is taken in normal doses. Side effects can be mild or severe, temporary or permanent.

The side effects listed below are not experienced by everyone who takes Tagrisso (Osimertinib). If you are concerned about side effects, discuss the risks and benefits of Tagrisso (Osimertinib) with your doctor.

The following side effects have been reported by at least 1% of people taking Tagrisso (Osimertinib). Many of these side effects can be managed, and some may go away on their own over time.

Contact your doctor if you experience these side effects and they are severe or bothersome. Your pharmacist may be able to advise you on managing side effects.

• Constipation
• cough
• decreased appetite
• Diarrhea
• dizziness
• dry, itchy skin
• fatigue
• hair loss
• headache
• mouth sores
• nausea
• nose bleeds
• runny or stuffy nose
• sinus or throat infections
• trouble concentrating
• vomiting
• weakness

Although most of the side effects listed below don't happen very often, they could lead to serious problems if you do not seek medical attention.
Check with your doctor as soon as possible if any of the following side effects occur:

• back pain
• blistering, peeling, redness, tingling or swelling of palms of hands or bottoms of feet
• bruise-like or raised marks on skin
• eye pain and sensitivity to light
• shortness of breath
• signs of Anemia (low red blood cells; e.g., dizziness, pale skin, unusual tiredness or weakness, shortness of breath)
• signs of an eye infection (e.g., itchy, swollen, red eyes with discharge)
• signs of clotting problems (e.g., unusual nosebleeds, bruising, blood in urine, coughing blood, bleeding gums, cuts that don 't stop bleeding)
• signs of infection (symptoms may include Fever or chills, severe diarrhea, shortness of breath, prolonged dizziness, headache, stiff neck, weight loss, or listlessness)
• signs of kidney problems (e.g., increased urination at night, decreased urine production, blood in the urine, change of urine colour)
• signs of heart problems (e.g., fast, irregular heartbeat or pulse, chest pain, sudden weight gain, difficulty breathing, leg swelling)
• signs of liver problems (e.g., nausea, vomiting, diarrhea, loss of appetite, weight loss, yellowing of the skin or whites of the eyes, dark urine, pale stools)
• skin and nail problems (itching, dry skin, rash, blisters around the nail, swelling, discolored, or detached nails)
• swollen eye lids
• symptoms of irregular heartbeat (e.g., chest pain; dizziness; rapid, pounding heartbeat; shortness of breath)
• symptoms of lung inflammation (e.g., shortness of breath, cough, chest pain, painful breathing, wheezing, tiredness, coughing up blood)
• vision problems

Stop taking the medication and seek immediate medical attention if any of the following occur:

• breathing problems (e.g., sudden worsening or shortness of breath, bluish colour of skin, lips or fingernails, irregular heartbeat, sleepiness, loss of consciousness)
• chest pain
• signs of a blood clot in the arm or leg (tenderness, pain, swelling, warmth, or redness in the arm or leg) or lungs (difficulty breathing, sharp chest pain that is worst when breathing in, coughing, coughing up blood, sweating, or passing out)
• signs of a serious allergic reaction (e.g., abdominal cramps, difficulty breathing, nausea and vomiting, or swelling of the face and throat)
• signs of a serious skin reaction (such as skin rash; red skin; blistering of the lips, eyes, or mouth; skin peeling; fever; or joint pain)

Some people may experience side effects other than those listed. Check with your doctor if you notice any symptom that worries you while you are taking Tagrisso (Osimertinib).

40 mg
Each beige, round, biconvex tablet marked with "AZ" and "40" on one side and plain on the other contains 40 mg of Tagrisso (Osimertinib). Nonmedicinal ingredients: mannitol, microcrystalline cellulose, low-substituted hydroxypropyl cellulose, and sodium stearyl fumarate; coating: polyvinyl alcohol, titanium dioxide, macrogol 3350, talc, yellow iron oxide, red iron oxide, and black iron oxide.

80 mg
Each beige, oval, biconvex tablet marked with "AZ" and "80" on one side and plain on the other contains 80 mg of Tagrisso (Osimertinib). Nonmedicinal ingredients: mannitol, microcrystalline cellulose, low-substituted hydroxypropyl cellulose, and sodium stearyl fumarate; coating: polyvinyl alcohol, titanium dioxide, macrogol 3350, talc, yellow iron oxide, red iron oxide, and black iron oxide.

Do not take Tagrisso (Osimertinib) if you are allergic to Tagrisso (Osimertinib) or any ingredients of the medication.

There may be an interaction between Tagrisso (Osimertinib) and any of the following:

• 5-ASA medications (e.g.,  Mesalamine, Olsalazine, Sulfasalazine)
• Aliskiren
• Amiodarone
• anti-cancer medications (e.g., Daunorubicin, Doxorubicin, Mitotane, Paclitaxel, Topotecan)
• antipsychotics (e.g., chlorpromazine, Clozapine, Haloperidol, Olanzapine, Quetiapine, Risperidone)
• Apalutamide
• "azole" antifungals (e.g., itraconazole, ketoconazole, Voriconazole)
• bacillus Calmette-Guérin (BCG)
• beta-2 agonists (long acting) (e.g., formoterol, salmeterol)
• birth control pills
• Bosentan
• chloroquine
• Colchicine
• corticosteroids (e.g., Dexamethasone, Hydrocortisone, Methylprednisolone)
• Cyclosporine
• dabigatran
• Deferasirox
• Digoxin
• Disopyramide
• diuretics (water pills; e.g., Furosemide, Hydrochlorothiazide, triamterene)
• Domperidone
• Doxepin
• Dronedarone
• echinacea
• Edoxaban
• efavirenz
• Elagolix
• Enzalutamide
• etravirine
• Everolimus
• Flecainide
• glecaprevir and pibrentasvir
• hydroxychloroquine
• laxatives
• Leflunomide
• lumacaftor and Ivacaftor
• macrolide antibiotics (e.g., clarithromycin, erythromycin)
• mefloquine
• Methadone
• Modafinil
• Morphine
• Nadolol
• Naloxegol
• Natalizumab
• Ozanimod
• pentamidine
• Primaquine
• procainamide
• Propafenone
• other protein kinase inhibitors (e.g., Dasatinib, imatinib, Nilotinib, Sunitinib)
• quinidine
• quinine
• quinolone antibiotics (e.g., ciprofloxacin, Norfloxacin, Ofloxacin)
• rifabutin
• rifampin
• rilpivirine
• ritonavir
• Romidepsin
• Rosuvastatin
• St. John's wort
• Sarilumab
• saquinavir
• seizure medications (e.g., Carbamazepine, Clobazam, Levetiracetam, Phenobarbital, Phenytoin, primidone, Topiramate, Valproic acid, zonisamide)
• selective serotonin reuptake inhibitors (SSRIs; e.g., Citalopram, Fluoxetine, Paroxetine, Sertraline)
• serotonin antagonists (anti-emetic medications; e.g., Granisetron, Ondansetron)
• siltuximab
• Sirolimus
• sotalol
• tacrolimus
• Tocilizumab
• Tolvaptan
• tricyclic antidepressants (e.g., Amitriptyline, Clomipramine, Desipramine, Trimipramine)
• vaccines
• Venlafaxine

If you are taking any of these medications, speak with your doctor or pharmacist. Depending on your specific circumstances, your doctor may want you to:

• stop taking one of the medications,
• change one of the medications to another,
• change how you are taking one or both of the medications, or
• leave everything as is.

An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.

Medications other than those listed above may interact with Tagrisso (Osimertinib). Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications you are taking. Also tell them about any supplements you take. Since caffeine, alcohol, the Nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them.

Before you begin using a medication, be sure to inform your doctor of any medical conditions or Allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should use Tagrisso (Osimertinib).

Abnormal heart rhythms: Tagrisso (Osimertinib) can cause abnormal heart rhythms. Certain medications (e.g., Sotalol, quinidine, thioridazine, Chlorpromazine, Pimozide, moxifloxacin, Mefloquine, pentamidine, arsenic trioxide, Tacrolimus) can increase the risk of a type of abnormal heart rhythm called QT prolongation, and should not be used in combination with Tagrisso (Osimertinib). You are more at risk for this type of abnormal heart rhythm and its complications if you:

• are female
• are older than 65 years of age
• have a family history of sudden cardiac death
• have a history of heart disease or abnormal heart rhythms
• have a slow heart rate
• have congenital prolongation of the QT interval
• have Diabetes
• have had a Stroke
• have low potassium, magnesium, or calcium levels
• have nutritional deficiencies

If you have heart disease and abnormal heart rhythms, or are taking certain medications (e.g., Verapamil, atazanavir), discuss with your doctor how Tagrisso (Osimertinib) may affect your medical condition, how your medical condition may affect the dosing and effectiveness of Tagrisso (Osimertinib), and whether any special monitoring is needed.

Birth control: If you or your partner could become pregnant, talk to your doctor about appropriate birth control while using Tagrisso (Osimertinib). Birth control pills may become less effective when taken during treatment with Tagrisso (Osimertinib). Men who are taking Tagrisso (Osimertinib) should not father a child while taking Tagrisso (Osimertinib) and for at least 4 months after completing treatment with Tagrisso (Osimertinib).

Drowsiness/reduced alertness: Tagrisso (Osimertinib) may cause dizziness, vision changes, or other side effects that affect your ability to drive or operate machinery. Avoid driving, operating machinery, or performing other potentially hazardous tasks until you have determined how Tagrisso (Osimertinib) affects you.

Eye problems: Tagrisso (Osimertinib) may cause eye inflammation. If you experience blurred vision, dry eyes, eye pain, swelling, redness with a gritty feeling, sensitivity to light, or any other eyesight changes, contact your doctor as soon as possible. Wearing contact lenses increases your risk of eye problems.

Heart problems: Tagrisso (Osimertinib) may cause or worsen symptoms of heart disease. If you have heart disease such as Congestive Heart Failure, or arrhythmia, discuss with your doctor how Tagrisso (Osimertinib) may affect your medical condition, how your medical condition may affect the dosing and effectiveness of Tagrisso (Osimertinib), and whether any special monitoring is needed. Contact your doctor as soon as possible if you develop symptoms of heart problems such as shortness of breath, chest pain, rapid heartbeat, or swollen ankles.

Liver function: Tagrisso (Osimertinib) is broken down by the liver. If you have liver problems, discuss with your doctor how Tagrisso (Osimertinib) may affect your medical condition, how your medical condition may affect the dosing and effectiveness of Tagrisso (Osimertinib), and whether any special monitoring is needed. Your doctor may want to test your liver function regularly with blood tests while you are taking Tagrisso (Osimertinib).

Lung inflammation: Lung inflammation (interstitial lung disease), causing difficulty breathing has occurred rarely for some people taking Tagrisso (Osimertinib). This complication can be serious and sometimes fatal. If you experience new or worsening shortness of breath or cough (with or without fever) at any time while you are taking Tagrisso (Osimertinib), contact your doctor immediately.

Pregnancy: Tagrisso (Osimertinib) may harm an unborn child if the mother takes it during pregnancy. Tagrisso (Osimertinib) should not be used during pregnancy unless the benefits outweigh the risks. Women who may become pregnant must use an effective birth control method while taking Tagrisso (Osimertinib) and for at least 2 months after taking the last dose of medication. If you become pregnant while taking Tagrisso (Osimertinib), contact your doctor immediately.

Breast-feeding: It is not known if Tagrisso (Osimertinib) passes into breast milk. If you are breast-feeding and are taking Tagrisso (Osimertinib), it may affect your baby. Talk to your doctor about whether you should continue breast-feeding.

Children: The safety and effectiveness of using Tagrisso (Osimertinib) have not been established for children and adolescents younger than 18 years of age.

Seniors: People over the age of 65 may experience side effects from taking Tagrisso (Osimertinib).