My son had the condition identical to what you are describing when he was 2 years old. We tried many different creams (prescribed by pediatrician) and it kept recurring for about 6 months. Then, it dissapeared after I applied Flagyl for a week (also prescribed). He was rash-free since then. Now I have 20 months old son with the same conditions. I am using tee tree oil on him and it seems to work. I apply very small amount around his mouth 2 times a day. Larger dose seem to cause burning sensation, so I apply only a little. The rash almost cleared in 1.5 week. Good luck to you!
Hello,
From the symptoms it looks like dermatitis to the foods/ baby creams or even constant wetness of the area due to saliva or drooling. Check out the tentative allergens to which the baby’s skin is exposed and apply a good hypoallergenic moisturizer over the area and see if this improves. If the symptoms still persist then you can apply calamine lotion as it also helps in soothing the skin.
If the irritation persists or is associated with any itching then please get it evaluated from a dermatologist. Perioral dermatitis and atopic dermatitis have to be ruled out.
Hope it helps. Take care and please do keep me posted on how you are doing or if you have any additional queries. Warm regards.