Some common symptoms of alternating hemiplegia are mental impairment, gait and balance difficulties, excessive sweating and changes in body temperature. Symptoms and signs
Superior alternating hemiplegia
Superior alternating hemiplegia (also known as Weber syndrome) has a few distinct symptoms: contralateral hemiparesis of limb and facial muscle accompanied by weakness in one or more muscles that control eye movement on the same side. Another symptom that appears is the loss of eye movement due to damage to the oculomotor nerve fibers. The upper and lower extremities have increased weakness. Middle alternating hemiplegia
Middle alternating hemiplegia (also known as Foville Syndrome) typically constitutes weakness of the extremities accompanied by paralysis of the extraocular muscle specifically lateral rectus, on the opposite side of the affected extremities, which indicates a lesion in the caudal and medial pons involving the abducens nerve root (controls movement of the eye) and corticospinal fibers (carries motor commands from the brain to the spinal cord). Inferior alternating hemiplegia
Inferior alternating hemiplegia (also known as medial medullary syndrome) typically involves a "weakness of the extremities accompanied by paralysis of muscles on the ipsilateral side of the tongue (seen as a deviation of the tongue on that side on protrusion). These symptoms indicate a lesion in the medulla involving the corticospinal fibers in the pyramid and the exiting hypoglossal nerve roots. Causes
Note that this description is focused on alternating hemiplegia of childhood. Similar syndromes may develop following a brainstem infarction. The cause of alternating hemiplegia of childhood is the mutation of ATP1A3 gene.
This occurrence is very indicative of alternating hemiplegia and as such those who display this are usually diagnosed with probable alternating hemiplegia. Fifth, indications of developmental delays, learning disability, or neurological irregularities are present. These issues may not be obvious in very young patients; however, it appears in almost all older patients. : 777  The final criteria before a diagnosis of alternating hemiplegia can be made is that all of these symptoms must not be due to another disorder. If the symptoms can be attributed to another disease or disorder, then a definitive diagnosis is difficult to make. : 778

Diagnosis of Webers syndrome
Webers syndrome is the only form of alternating hemiplegia that is somewhat easy to diagnose beyond the general criteria. Although Webers syndrome is rare, a child born with the disorder typically has a port-wine stain on the face around the eye. While the port-wine stain does not necessarily mean the child has Webers syndrome, if the port-wine stain involves the ophthalmic division of the trigeminal nerve than the likelihood of it being webers syndrome greatly increases. If a port-wine stain around the eye is found, the patient should be screened for intracranial leptomeningeal angiomatosis. Magnetic resonance imaging (MRI) can be used to determine the presence and severity while computed cranial tomography can be used to determine the effect. MRI is the preferred diagnostic test on children presenting with port-wine stain. Other imaging techniques can be used in addition to further determine the severity of the disorder.