What can you use for garlic burns on the skin, to decrease the redness and scarring?

See derm: It depends on whether there are blisters or open areas. You should see dermatologist for the correct treatment.

Garlic not advised: The best treatment for burns is an antibiotic ointment like silvadene (silver sulfadiazine) or bacitracin. Keeping the wound clean and moist with an antibiotic ointment will provide the most reliable results. Plant extracts not only smell (as in the case of garlic) but can be irritating.