What is the treatment for granuloma?

If the foreign substance that is causing the granuloma is oil based (like vaseline or mineral oil), a 6-week course of corticosteriods (like spironolactone) have been shown to reduce and even eliminate the granuloma, so see a dermatologist.

Also, try applying a hot pad to affected area 4 times a day for 15-30 minutes along with a topical product (see below), to break down the oil, and make sure to avoid cold temperatures to the affected area. Several products that you can apply topically will break down oil/petroleum-based substances in the skin. These are noxema, tea tree oil, and castor oil (applying these products with heat can work especially well). Pure (100%) tea tree oil works best, but it will dry out the skin which can cause dermatitis, so apply sparingly to start to see how your skin reacts. Noxema and castor oil don't irritate the skin. Note - you will have to do this consistently for at least 6 weeks along with cortiocosteriods to see any real results.