Walgreens has 4-oz Zarbee's Naturals Children's Cough Syrup + Mucus with Dark Honey & Ivy Leaf (Natural Grape) on sale 2 for $5.10. Free store pickup on $10+. [amazon]
Login Walgreen account > Go to product page > Clip $3 off > add 2 x to cart > Apply code "WAG10" at checkout
Amazon has 40% off 1st subscribe coupon (YMMV) for select Zarbee's Kids Cough + Mucus on sale. Plus extra 5% off with subscribe.