Sensitivity is often different between ears. Noxacusis (Pain Hyperacusis)
In some instances, hyperacusis is accompanied by pain, which is known as noxacusis. Noxacusis is characterized by pain resulting from sounds, often initiated at certain volumes or frequencies; pain can be immediate or delayed, and sometimes persists for an extended period of time following exposure. Pain can be acute or chronic, and is often described as stabbing, burning, acid, or nerve pain, and is sometimes equated with the pain of a root canal or a broken tooth. Loudness Discomfort Level (LDL)
The threshold of sound at which discomfort is initially experienced; measured in decibels (dB). Setback
After a period of some relief from symptoms, discomfort resumes; often resulting from exposure to sound, or, in some cases, ototoxic medications or injuries. Setback prevention is an important focus among those affected. Associated conditions
Some conditions that are associated with hyperacusis include:

Causes
The most common cause of hyperacusis is overexposure to excessively high decibel (sound pressure) levels.Some affected people acquire hyperacusis suddenly as a result of taking ear sensitizing drugs, Lyme disease, Ménières disease, head injury, or surgery. Others are born with sound sensitivity, develop superior canal dehiscence syndrome, have had a history of ear infections, or come from a family that has had hearing problems. Bells palsy can trigger hyperacusis if the associated flaccid paralysis affects the tensor tympani, and stapedius, two small muscles of the middle ear. Paralysis of the stapedius muscle prevents its function in dampening the oscillations of the ossicles, causing sound to be abnormally loud on the affected side.
In ophthalmology, accommodative excess (also known as excessive accommodation or accommodation excess) occurs when an individual uses more than normal accommodation (focusing on close objects) for performing certain near work. Accommodative excess has traditionally been defined as accommodation that is persistently higher than expected for the patients age. Modern definitions simply regard it as an inability to relax accommodation readily. Excessive accommodation is seen in association with excessive convergence also. Symptoms and signs
Blurring of vision due to pseudomyopia
Headache
Eye strain
Asthenopia
Trouble concentrating when reading

Causes
Causes related to refractive errors
Accommodative excess may be seen in the following conditions:
Hypermetropia: Young hypermetropes use excessive accommodation as a physiological adaptation in the interest of clear vision. Myopia: Young myopes performing excessive near work may also use excessive accommodation in association with excessive convergence. Astigmatism: Astigmatic eye may also be associated with accommodative excess. Presbyopia: Early presbyopic eye may also induce excessive accommodation. Improper or ill fitting spectacles: Use of improper or ill fitting spectacles may also cause use of excessive accommodation. Causes related to systemic drugs
Use of systemic drugs like Morphine, Digitalis, Sulfonamides, Carbonic anhydrase inhibitors may cause accommodative excess. Causes related to diseases
Unilateral excessive accommodation-Trigeminal neuralgia, and head trauma may cause ciliary spasm and may cause accommodative excess. Bilateral excessive accommodation-Diseases like Encephalitis, Syphilis, Head trauma, Influenza, Meningitis may cause ciliary spasm and bilateral excessive accommodation. Secondary to Convergence insufficiency
Accommodative excess may occur secondary to convergence insufficiency also. In convergence insufficiency near point of convergence will recede, and positive fusional vergence (PFV) will reduce.