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 Mekinist (Trametinib). If you are concerned about side effects, discuss the risks and benefits of Mekinist (Trametinib) with your doctor.

The following side effects have been reported by at least 1% of people taking Mekinist (Trametinib). 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
• Diarrhea
• Dry Mouth
• hair loss or thinning
• headache
• increased sensitivity of the skin to light
• lack of energy
• nausea
• pain or peeling skin of the hands or feet
• stomach ache
• swelling hands or feet
• vomiting
• weakness/tiredness

Although most of the side effects listed below don't happen very often, they could lead to serious problems if you do not check with your doctor or seek medical attention.

Check with your doctor as soon as possible if any of the following side effects occur:

• acne-like rash
• changes to fingernails and toenails (e.g., pain, infection, swelling)
• changed urine output
• dehydration (e.g., decreased urine, dry skin, dry and sticky mouth, sleepiness, dizziness, headache, thirst, confusion)
• dry, chapped, and cracked or itching skin
• facial swelling
• fast, slow, or pounding heartbeat
• flu-like symptoms (e.g., tiredness, chills, sore throat, joint or muscle aches)
• increased blood pressure
• signs of Anemia (low red blood cells; e.g., dizziness, pale skin, unusual tiredness or weakness, shortness of breath)
• signs of bleeding (e.g., bloody nose, blood in urine, coughing blood, bleeding gums, cuts that don't stop bleeding)
• signs of heart failure (e.g., fast, irregular heartbeat or pulse, dizziness, difficulty breathing, swollen legs, feet)
• 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 muscle damage (e.g., muscle pain, tenderness or weakness, or brown or discoloured urine), especially if you also have a fever or a general feeling of being unwell
• skin changes (e.g., rash, discolouration, thickening, infection, Warts, pus-filled blisters)
• skin sore, wart, or bump that does not heal
• skin rash
• urinary tract infection (e.g., pain when urinating, urinating more often than usual, low back or flank pain)
• vision changes (coloured dots, halos around objects, blurred or reduced vision)

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

• signs of bleeding in the stomach (e.g., bloody, black, or tarry stools; spitting up of blood; vomiting blood or material that looks like coffee grounds)
• 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 inflammation of the lungs (e.g., shortness of breath and cough)
• signs of a serious allergic reaction (e.g., abdominal cramps, difficulty breathing, nausea and vomiting, or swelling of the face and throat)
• signs of pancreatitis (e.g., abdominal pain on the upper left side, back pain, nausea, fever, chills, rapid heartbeat, swollen abdomen)
• symptoms of high blood sugar (excessive thirst or hunger, excessive urination, weight loss, tiredness)

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 Mekinist (Trametinib).

0.5 mg
Each yellow, modified oval, biconvex, film-coated tablet with "GS" debossed on one face and "TFC" on the other contains 0.5 mg of Mekinist (Trametinib). Nonmedicinal ingredients: croscarmellose sodium, hypromellose, magnesium stearate, mannitol, microcrystalline cellulose, silicon dioxide (colloidal), and sodium lauryl sulphate; coating: hypromellose, polyethylene glycol, iron oxide yellow, and titanium dioxide.

2 mg
Each pink, round, biconvex, film-coated tablet with "GS" debossed on one face and "HMJ" on the other contains 2 mg of Mekinist (Trametinib). Nonmedicinal ingredients: croscarmellose sodium, hypromellose, magnesium stearate, mannitol, microcrystalline cellulose, silicon dioxide (colloidal), and sodium lauryl sulphate; coating: hypromellose, polyethylene glycol, iron oxide red, polysorbate 80, and titanium dioxide.

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

There may be an interaction between Mekinist (Trametinib) and any of the following:

• Amiodarone
• beta-adrenergic blockers (e.g., Atenolol, Propranolol, Sotalol)
• dabrafenib
• Digoxin
• HIV protease inhibitors (e.g., atazanavir, indinavir, ritonavir, saquinavir)
• procainamide
• quinidine
• sotalol

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 Mekinist (Trametinib). 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 Mekinist (Trametinib).

Birth control: Women taking Mekinist (Trametinib) who could become pregnant must use effective birth control while taking Mekinist (Trametinib) and for 16 weeks after the last dose. When Mekinist (Trametinib) is taken along with the medication dabrafenib, birth control pills, patches, and injections are not as effective and other birth control methods must be used. Men taking Mekinist (Trametinib) who have partners who are or may become pregnant should use condoms with spermicide as birth control while taking Mekinist (Trametinib) and for 16 weeks after taking the last dose.

Bleeding: Mekinist (Trametinib) may increase your risk of bleeding. If you have a history of coughing up blood, brain bleeds, or bleeding from the stomach, discuss with your doctor how Mekinist (Trametinib) may affect your medical condition. If you notice signs of serious bleeding, such as vomiting blood or a coffee grounds-like substance, or bleeding from the rectum, get immediate medical attention.

Blood Clots: Mekinist (Trametinib) appears to increase the risk of developing blood clots. These blood clots may form anywhere in the body, but are more noticeable when they occur in the large muscles, lung, brain (Stroke), or heart (Heart Attack). If you experience pain in the chest or leg, unexplained shortness of breath, fast and irregular heartbeat, severe headache, blurred vision, or slurred speech, get immediate medical attention.

Diabetes: Mekinist (Trametinib) may cause increases in blood sugar levels. If you have diabetes, monitor your blood sugar frequently as recommended by your doctor. If you experience symptoms of high blood sugar (e.g., increased urination, increased thirst, increased eating, and weakness) while taking Mekinist (Trametinib), contact your doctor.

Eye problems: There have been rare reports of retinal detachment and retinal vein occlusion (blockage of the vein draining the eye) from people taking Mekinist (Trametinib). If you notice any changes in your vision such as coloured dots, halos, or blurred vision, contact your doctor immediately.

Gastrointestinal problems: Rarely, Mekinist (Trametinib) can cause inflammation of the digestive tract (colitis) or perforation of the stomach or intestines. If you experience severe abdominal pain, fever, vomiting, nausea, or black and tarry stools, contact your doctor immediately.

Heart problems: Mekinist (Trametinib) may cause the heart to become less effective in pumping blood out into the body. It may also cause severely decreased heart rate. If you have a history of heart disease or are at risk of developing heart disease, discuss with your doctor how Mekinist (Trametinib) may affect your medical condition, how your medical condition may affect the dosing and effectiveness of Mekinist (Trametinib), and whether any special monitoring is needed.

If you experience signs of decreased heart function, like a change in heartbeat or pulse, chest pain, difficulty breathing, unusual tiredness, or swelling in the legs, feet, or hands, contact your doctor as soon as possible.

High blood pressure: Mekinist (Trametinib) may increase your blood pressure. Your doctor will monitor your blood pressure while you are taking Mekinist (Trametinib).

Infection: As with other medications used to treat cancer, Mekinist (Trametinib) can cause a decrease in the number of white blood cells, the cells responsible for fighting infection in the body. Your doctor will have you go for regular blood work to monitor your white blood cells, however if you notice that you are getting infections more often, talk to your doctor as soon as possible.

Lungs: Mekinist (Trametinib) is known to cause serious lung and breathing problems. The resulting damage to the lungs can be fatal. If you experience any new or worsening cough or shortness of breath while using Mekinist (Trametinib), contact your doctor immediately. Your doctor may order a chest X-ray before you start using Mekinist (Trametinib) to use as a baseline in case you develop breathing problems.

Muscle effects:  Muscle damage has been associated with the use of Mekinist (Trametinib). Report any unexplained muscle pain, tenderness, weakness or cramps, or any brown or discoloured urine to your doctor immediately, particularly if you are also experiencing malaise (a general feeling of being unwell) or fever.

Skin problems: Mekinist (Trametinib) can cause additional skin problems such as rash, skin ulcers that may become infected, and other skin redness and irritation. These reactions can lead to serious problems. Let your doctor know as soon as possible if you develop any skin reactions while you are taking Mekinist (Trametinib).

Vision changes: Mekinist (Trametinib) may cause changes to the sharpness of your vision and possibly cause vision loss. Vision loss can occur slowly or suddenly. People with high blood pressure, diabetes, high blood cholesterol, or Glaucoma are at a higher risk of vision loss. Your doctor may order an eye exam before you start taking Mekinist (Trametinib). If you notice any change in your vision such as colour dots, a blurred outline around objects (halo), or blurred vision while you are taking Mekinist (Trametinib), contact your doctor immediately.

Pregnancy: Mekinist (Trametinib) may cause harm to an unborn child and should not be used during pregnancy. If you become pregnant while taking Mekinist (Trametinib), contact your doctor immediately. Women of childbearing age who are taking Mekinist (Trametinib) should use an effective method of birth control such as condoms during treatment and for 4 months after stopping the medication.

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

Children: The safety and effectiveness of using Mekinist (Trametinib) have not been established for children.