Commute 45 to 59 min. 7.20%. Commute greater than 60 min.
1 Oral Ulcers: Usually, an ulcer is referred to as an open wound which is formed inside the mouth and this occurs due to the invasion of micro organisms. 2  Sometimes, blood blisters are caused due to the skin infections caused as a side effect of medications. 3  Ulcers are of two types they are: Canker sores and Cold sores.
Injury to the lip generally causes blood blisters on the lip, states Lip Source. An injury may include pinched or bitten skin. Blood pools under the injured skin causing the blood blister.