[4][5] The most common side effects include rash, diarrhea, tiredness, peripheral edema (swelling, especially of ankles and feet), nausea and acneiform dermatitis (acne-like inflammation of the skin).

[5] When taken in combination with dabrafenib the most common side effects include fever, tiredness, nausea, chills, headache, diarrhea, vomiting, joint pain and rash.

[5] In May 2013, trametinib was approved as a single-agent by the US Food and Drug Administration for the treatment of people with V600E mutated metastatic melanoma.

[11] As a result of this research, on 8 January 2014, the FDA approved the combination of dabrafenib and trametinib for the treatment of patients with BRAF V600E/K-mutant metastatic melanoma.

[6][7] Trametinib had good results for metastatic melanoma carrying the BRAF V600E mutation in a phase III clinical trial.