MDA Sulfur/ Sal Acid/ Tea Tree 2% Wash MDA Sale! from 1700 /per Qty. Add to Cart This item is currently on backorder but you can still purchase it now and we'll ship as soon as more become available. Sulfuric Acid and Tea Tree based wash for use on scalp or body 2-3x weekly. This cleanser is optimal for patients with seborrheic dermatitis (flaky scalp) acne, and dry skin.