TAFINLAR ® (dabrafenib) capsules + MEKINIST ® (trametinib) tablets may cause serious side effects, including:. Risk of new cancers: TAFINLAR, when used in combination with MEKINIST, may cause a type of skin cancer called cutaneous squamous cell carcinoma, keratoacanthoma, basal cell carcinoma, or melanoma. Talk with your health care provider about your risk for these cancers.