Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat. Call your doctor at once if you have a serious side effect such as: Pale skin, feeling light-headed or short of breath, rapid heart rate, trouble concentrating; or severe skin reaction — fever, sore throat, swelling in your face or tongue, burning in your eyes, skin pain, followed by a red or purple skin rash that spreads (especially in the face or upper body) and causes blistering and peeling. Less serious side effects may include: Tired feeling; nausea, vomiting, diarrhea, altered sense of taste; rectal itching, burning, or discomfort; or mild skin rash.

Incivek is known to have serious or life-threatening reactions with certain medications such as some cholesterol-lowering medications and some medications prescribed for heart health. Do not take Incivek if you are pregnant or may become pregnant, or if you are a man with a sexual partner who is pregnant. You must have a negative pregnancy test before starting treatment, every month during treatment, and for six months after your treatment ends. Tell your doctor if you are breastfeeding. It is not known if Incivek passes into your breast milk. You and your healthcare provider should decide if you will take Incivek or breastfeed. You should not do both.