Effect of chronic propranolol on growth of newborn beagle puppies

To evaluate the effect of chronic propranolol on body growth and organ size, newborn beagle puppies were assigned to each of three treatment groups: high propranolol (18 mg/kg/day); low propranolol (6 mg/kg/day), and control. Heart rate and systolic blood pressure were significantly lower in animals receiving propranolol (p less than 0.001). There were no significant differences between groups at any time during the 6 months of observation in length, weight and necropsy wet weights or histology of brain, heart, kidney, lung, liver, thyroid, pancreas, adrenal, pituitary, prostate or gonad, or in humerus and femur length. Chronic propranolol therapy had no apparent effect on body growth and individual organ size of normal newborn beagle puppies.