Don't paint your brick, stain it. With staining it allows the brick to breath and it's less maintenance and upkeep.

Where as if you paint the brick, water and moisture can become trapped behind it and start to deteriorate the brick. It will swell up, leach calcium and other minerals, and eventually crumble.

"Using the wrong type of paint, or not noticing chips or cracks in the paint can trap moisture in the porous bricks and cause mold or a breakdown of the brick. Brick experts agree that to correctly maintain your painted brick, it should be repainted every 3-5 years."

Source: http://beckiowens.com/pros-and-cons-painted-brick-exteriors/

Actually there are mineral based brick paints that dont require any more maintanence than other housepaints would on siding. That way you only need to paint every 20 years. I like the top option.