Flu blisters on lips

Cold sores often begin with tingling, then form grouped fluid-filled vesicles on the lip border that crust. Canker sores, impetigo, allergy, trauma, and lesions inside the mouth can look different.

Keep the area clean, avoid picking, wash hands after touching it, and avoid kissing or sharing lip products while active. Early antiviral treatment may be considered by a clinician.

Seek care if the lesion is near the eye, widespread, very painful, slow to heal, recurrent, or associated with fever, dehydration, or immune suppression.

Ask whether it looks like a cold sore, whether testing is needed, when antiviral treatment helps, and how to limit contact transmission.