Episodic Falling Syndrome (EFS) is an inherited condition affecting Cavalier King Charles Spaniels. Episodes usually begin between 14 weeks and 4 years of age and are often associated with exercise, excitement or frustration. However, these episodes can occur at any time or under any circumstance. EFS is a disorder of the muscles that causes increased muscle tone and muscle spasticity (especially those of the limbs) resulting in limbs that appear “locked” in an extended position. This muscle spasticity results in a characteristic “praying” position and/or collapse. Episodes are usually a few seconds to several minutes in length and resolve on their own. Affected dogs appear neurologically normal between episodes. The severity and number of episodes vary over the course of the dog’s life and do not follow a specific progression pattern.