Dopamine deficiency is sort of a myth but I still think this is a funny metaphor for pleasure-seeking, a thing you should definitely do, because pleasure is good for you! (btw that is a Roseate Spoonbill, the unofficial Queer Vengeance mascot.)
Give Me The Dopamine Tee
Shirts are created using the Direct-To-Garment printing process. It might smell chemically at first but that's normal! Turn the shirt inside out when you wash it on cold and air dry or tumble dry low to keep the print looking fresh.