Mekinist (trametinib) is a targeted therapy that’s taken with another medication called Tafinlar (dabrafenib). It’s used to treat many types of cancer that have a certain mutation known as a BRAF mutation. Mekinist (trametinib) is a tablet that you take by mouth once daily. This medication can cause side effects such as diarrhea, rash, and high blood sugar.
Melanoma with certain BRAF mutations
Melanoma that has spread (metastatic) or can’t be removed by surgery, used by itself or with Tafinlar (dabrafenib)
Advanced melanoma, given after surgery and used with Tafinlar (dabrafenib)
Metastatic non-small cell lung cancer (NSCLC) with a certain BRAF mutation, used with Tafinlar (dabrafenib)
Metastatic anaplastic thyroid cancer (ATC) with a certain BRAF mutation, used with Tafinlar (dabrafenib)
Solid tumors with a certain BRAF mutation that have spread or can’t be removed by surgery, used with Tafinlar (dabrafenib)
Low-grade glioma (LGG) with a certain BRAF mutation, used with Tafinlar (dabrafenib)
Mekinist (trametinib) is a kinase inhibitor known as a MEK inhibitor. The MEK protein is part of a whole chain of proteins that work to help cells grow. By blocking MEK, this medication helps stop tumor growth.
Mekinist (trametinib) is taken together with an anticancer medication called Tafinlar (dabrafenib) that specifically targets another protein in this chain (the BRAF protein). When the BRAF protein is mutated, the cancer can grow uncontrollably and spread more quickly. By blocking two different proteins in this pathway, Mekinist (trametinib) and Tafinlar (dabrafenib) work together to stop the growth and spread of cancer better.
Source: DailyMed
Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.
Check with your doctor immediately if any of the following side effects occur:
More common
Bleeding from the rectum or bloody stools
bleeding gums
blemishes on the skin
blistering, crusting, irritation, itching, or reddening of the skin
bloating or swelling of the face, arms, hands, lower legs, or feet
bloody nose
blurred vision
chest discomfort or pain
cracked, dry, or scaly skin
coughing up blood
decreased urine output
difficulty with breathing or swallowing
dilated neck veins
extreme tiredness or weakness
fast, slow, irregular, or pounding heartbeat
headache
increased menstrual flow or vaginal bleeding
irregular breathing
lightheadedness, dizziness, or fainting
nervousness
nosebleeds
paralysis
pounding in the ears
prolonged bleeding from cuts
rapid weight gain
rash
red or black, tarry stools
red or dark brown urine
redness, swelling, or pain of the skin
scaling of the skin on the hands and feet
tightness in the chest
tingling of the hands and feet
ulceration of the skin
unusual tiredness or weakness
unusual weight gain or loss
Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:
More common
Burning, itching, and pain in hairy areas, pus at the root of the hair
change in taste
dark urine
itching, pain, redness, swelling, tenderness, or warmth on the skin
loosening of the fingernails
loss of taste
muscle cramp, pain, stiffness, or spasm
redness or soreness around the fingernails
sores, ulcers, or white spots on the lips or tongue or inside the mouth
swelling or inflammation of the mouth
thirst
Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.
Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.
Recommended treatment option for certain people with melanoma, NSCLC, ATC, and low-grade glioma that have the BRAF mutation
Taken by mouth (not an injection that requires needles)
Works in a more specific, targeted way than traditional chemotherapy
Liquid solution available for young children with low-grade glioma or solid tumors who require exact doses
Must take with a second medication
Must take on an empty stomach
Requires regular blood tests to check for side effects
Can cause fever
You should take Mekinist (trametinib) on an empty stomach (1 hour before or 2 hours after a meal). The medication might not work as well if you take it with food.
Contact your provider if you have a fever, even if you don’t have other symptoms such as tiredness or chills. A fever that happens while you’re taking Mekinist (trametinib) can be serious.
If you have diarrhea while you’re taking Mekinist (trametinib), make sure you drink plenty of fluids. But avoid sugary sports drinks because they can make diarrhea worse. If needed, your provider might recommend over-the-counter diarrhea medications, like loperamide (Imodium A-D), to help.
If you also have diabetes, contact your provider if your blood sugar level is higher than what’s typical for you. Taking Mekinist (trametinib) and Tafinlar (dabrafenib) can sometimes raise your blood sugar levels. For this reason, your provider will keep track of your blood sugar levels more closely during treatment.
Women who are taking Mekinist (trametinib) should avoid breastfeeding during treatment and for 4 months after the last dose. We don’t know whether Mekinist (trametinib) is found in breast milk and whether it affects breastfed babies, but there’s a possible risk of harm to a baby.
If you have leftover medication, ask your provider how to dispose of it. They might allow you or a family member to bring it to their office or clinic for proper disposal.
Tips for the Mekinist (trametinib) tablets:
Don’t crush or break the tablets.
Store the tablets in the refrigerator between 36 and 46 degrees Fahrenheit. Keep the medication in its original bottle; don’t put the tablets into a pill box.
Tips for the Mekinist (trametinib) oral solution:
Store the solution in the original bottle at room temperature (at no more than 77 degrees Fahrenheit). Don’t refrigerate the medication.
Make sure to only use the oral dosing syringe that comes with the packaging to measure out doses; household spoons might not be accurate.
Don’t use any extra solution 35 days after it was mixed (this date should be written on the bottle by the pharmacist). Ask your provider how to best discard any leftover medication.
Mekinist (trametinib) can cause some serious health issues. This risk may be even higher for certain groups. If this worries you, talk to your doctor or pharmacist about other options.
Some people taking Mekinist (trametinib) together with Tafinlar (dabrafenib) developed a new cancer. In studies, these cancers included different kinds of skin cancer. Your provider will check for new signs and symptoms of cancers while you’re taking Mekinist (trametinib). In particular, they’ll check for skin cancer during treatment and for up to 6 months after you stop therapy. Periodically performing skin checks yourself can be helpful as well.
Mekinist (trametinib), taken with Tafinlar (dabrafenib), can cause bleeding. This can include nosebleeds, bleeding in the gut, and rarely, bleeding in the brain. If you have any unusual bleeding, tell your provider right away. If it’s mild, your provider might pause Mekinist (trametinib) and you might be able to restart it later at a lower dose. But sometimes, the medication must be permanently stopped.
Rarely, Mekinist (trametinib) can cause tears in the gut or swelling in the gut (colitis). Seek medical help right away if you experience sudden or severe stomach pain, severe diarrhea, nausea, vomiting, fever, or chills. You might have to pause or stop Mekinist (trametinib) while your provider figures out the cause.
A small number of people have developed blood clots while taking Mekinist (trametinib) and Tafinlar (dabrafenib). These blood clots can include those that happen in the arm or leg (deep vein thrombosis or DVT). More seriously, blood clots have also happened in the lung (pulmonary embolism or PE). Get medical attention as soon as possible if you have sudden chest pain, trouble breathing, or swelling in one arm or leg. These can be signs that you have a blood clot.
Though uncommon, some people taking Mekinist (trametinib) with Tafinlar (dabrafenib) developed a heart condition where their heart doesn’t pump as well. Some people with this condition might not feel anything. But others might have symptoms like tiredness, trouble breathing, and swelling in the legs. Your provider will monitor how well your heart is pumping through imaging called an echocardiogram (echo). You’ll usually need imaging scans of your heart every 2 to 3 months while you’re taking Mekinist (trametinib). If the scans show that your heart isn’t pumping as well as it should or if you experience related symptoms while you’re taking Mekinist (trametinib), you might need to pause or stop the medication.
While rare, treatment with Mekinist (trametinib) can cause eye problems, such as blood clots in the eye veins or retinal detachment. Your provider might refer you to an ophthalmologist while you’re taking Mekinist (trametinib). Tell your provider right away if you have any vision changes during treatment so they can check your eyes for any problems.
Rarely, some people taking Mekinist (trametinib) have developed a serious lung problem called interstitial lung disease (ILD). Talk to your provider as soon as possible if you experience sudden or worsening cough, trouble breathing, and fever. You might have to pause or stop Mekinist (trametinib) while your provider figures out what’s going on.
People taking Mekinist (trametinib) have developed a serious reaction with fever. Sometimes, fever is the only symptom; other times, people also experience chills, low blood pressure, and dehydration. If you have a fever of 100.4 degrees Fahrenheit or higher, contact your provider right away. You’ll probably need to stop taking the medication until your fever goes away. If you’re able to restart the medication, your provider might recommend you take medications to lower your temperature, like acetaminophen (Tylenol), to prevent serious fevers.
Rashes are common and aren’t usually serious for people taking Mekinist (trametinib) with Tafinlar (dabrafenib). But rarely, this medication can also cause severe skin reactions (with or without infections) that can be life-threatening, such as Stevens-Johnson syndrome (SJS) or drug reaction with eosinophilia and systemic symptoms (DRESS). Tell your provider right away if you develop painful blisters, skin wounds, or peeling skin, as these are signs of a serious skin reaction that need immediate medical attention.
Risk factors: Diabetes
Some people with diabetes who took Mekinist (trametinib) with Tafinlar (dabrafenib) had higher blood sugar levels. Sometimes, this effect requires starting or changing their diabetes medication to help manage blood sugar. Your provider will check your blood sugar levels while you’re taking Mekinist (trametinib), especially if you have diabetes. If you check your blood sugar at home and notice higher levels, contact your provider right away.
Rarely, people taking Mekinist (trametinib) with Tafinlar (dabrafenib) developed a serious blood condition called hemophagocytic lymphohistiocytosis (HLH). HLH might cause fever, low white blood cells, low red blood cells, and damage to organs such as the kidneys and liver. Seek medical attention right away if you have fever; swollen lymph nodes; or a tender, swollen stomach.
Based on animal studies, Mekinist (trametinib) might harm an unborn baby or raise the risk for miscarriage (pregnancy loss). Because of these risks, if you or your partner can get pregnant, you should use birth control while taking Mekinist (trametinib) and for 4 months after the last dose. Let your provider know right away if you or your partner becomes pregnant while you’re taking Mekinist (trametinib).
Adults: The typical dose is 2 mg by mouth once a day.
Children: The dose depends on your child’s body weight. The typical dose ranges from 0.3 mg to 2 mg by mouth once a day.
Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. Tell your healthcare professional if you are taking any other prescription or nonprescription (over-the-counter [OTC]) medicine.
Melanoma with certain BRAF mutations
Melanoma that has spread (metastatic) or can’t be removed by surgery, used by itself or with Tafinlar (dabrafenib)
Advanced melanoma, given after surgery and used with Tafinlar (dabrafenib)
Metastatic non-small cell lung cancer (NSCLC) with a certain BRAF mutation, used with Tafinlar (dabrafenib)
Metastatic anaplastic thyroid cancer (ATC) with a certain BRAF mutation, used with Tafinlar (dabrafenib)
Solid tumors with a certain BRAF mutation that have spread or can’t be removed by surgery, used with Tafinlar (dabrafenib)
Low-grade glioma (LGG) with a certain BRAF mutation, used with Tafinlar (dabrafenib)
Melanoma with certain BRAF mutations that has spread (metastatic) or can’t be removed by surgery; used with Braftovi (encorafenib)
Metastatic non-small cell lung cancer (NSCLC) with certain BRAF mutations; used with Braftovi (encorafenib)
Melanoma with certain BRAF mutations that has spread (metastatic) or can’t be removed by surgery, used together with Zelboraf (vemurafenib)
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