NO FISH OIL - To treat another condition I had been taking Cod Liver Oil (CLO 1500mg) and occasionally coconut oil (1000mg). Reading about Krill Oil I then added that (2000mg) and took the other two more regularly. My skin became a bit dryer but I thought it was from my heater being on overnight due to fall/winter weather. Then I developed the cracked corner lips and thinking I was just dehydrated expected them to heal with extra water over a day or two. A week later it hadn't healed and I knew something was wrong.
Thinking it was an infection, I tried tea tree oil or grapeseed oil, along with castor oil and then Listerine before bed. It would help overnight but return by the end of the next day.
I then thought about my diet. The only significant change I had to my diet was the addition of the Krill oil, and increase in CLO and Coconut oil. Doing research on Angular Cheilitis I found this:
"In general, dietary intake of natural, vitamin A rich sources like fish oils and cod liver oil increases the risk of developing angular cheilitis."
I immediately stopped all the other oils and started a Primrose Oil (1000mg to reduce inflammation) along with a B-50 complex twice a day. I would also poke a Vitamin E capsule and squeeze the contents onto my lips like a lip gloss. In the morning and evenings I'd drink a great Detox tea with dandelion root, licorice root, burdock, and other great liver supporting elements.
The condition began healing overnight. It took 3-4 days to completely exfoliate and renew the skin, but it's healed completely.
If your diet or location has changed in the past few months your system may be out of balance from changes in food and/or water sources. If you're taking supplements, optional medications, or beverages you may want to stop, detox and go vegan/green for a few weeks. And be patient. Healing from the outside in takes time; and the more out of balance your system, the longer the wait.