Huggable pituitary plush toy is 10.5" wide x 8" tall x 3.5” thick. Facts and educational information included with pituitary pillow.. Love, life and much more are all in your head -- thanks to the pituitary! Even though the pituitary is just a tiny little pea-sized nubbin dangling beneath your brain, he is known as the master gland because he controls all of the other endocrine glands (however, it is controlled, in turn, by the hypothalamus). His main functions include stimulating growth, regulating blood pressure, sex hormones, metabolism and water regulation. It’s one busy gland.