Progressive bulbar palsy (PBP) is a medical condition. It belongs to a group of disorders known as motor neuron diseases. PBP is a disease that attacks the nerves supplying the bulbar muscles. These disorders are characterized by the degeneration of motor neurons in the cerebral cortex, spinal cord, brain stem, and pyramidal tracts. This specifically involves the glossopharyngeal nerve (IX), vagus nerve (X), and hypoglossal nerve (XII).
This disorder should not be confused with pseudobulbar palsy or progressive spinal muscular atrophy. The term infantile progressive bulbar palsy is used to describe progressive bulbar palsy in children. The ICD-11 lists progressive bulbar palsy as a variant of amyotrophic lateral sclerosis (ALS).