Temporomandibular Joint (TMJ) Disorder: This condition is a common cause of pain behind the ear, especially if the pain is throbbing and associated with jaw movements or teeth grinding.

Tension Headache: Tension headaches can cause pain that radiates to the area behind the ear, often described as a throbbing or dull ache.
Ear Infection (Otitis Media or Otitis Externa): Infections of the middle or outer ear can cause pain behind the ear, which may be throbbing in nature, especially if there is an associated fever or discharge.
Mastoiditis: An infection of the mastoid bone, located behind the ear, can cause throbbing pain in this area, often accompanied by fever and swelling.

Temporal Arteritis (Giant Cell Arteritis): Although less common, this condition is critical to diagnose due to the risk of blindness if left untreated. It typically presents with headache, jaw claudication, and visual disturbances in older adults.
Meningitis: Inflammation of the protective membranes covering the brain and spinal cord can cause severe headache, including pain behind the ear, along with fever, stiff neck, and altered mental status.
Stroke or Transient Ischemic Attack (TIA): While less common, pain behind the ear can be a symptom of a stroke or TIA, especially if accompanied by other neurological deficits such as weakness, numbness, or difficulty with speech.

Trigeminal Neuralgia: A chronic pain condition that affects the trigeminal nerve, which can cause intense, shock-like or stabbing pain in parts of the face, including the area behind the ear, though this is less common.
Occipital Neuralgia: Involves the occipital nerves and can cause sharp, stabbing, or throbbing pain in the back and base of the skull, including the area behind the ear.
Eagle Syndrome (Styloid Process Syndrome): A rare condition where an elongated styloid process or calcified stylohyoid ligament causes pain in the face and ear area, including behind the ear, often accompanied by dysphagia.