The hearing loss is said to be iatrogenic (doctor caused)

Ototoxic drugs can be:
    1.  Cochleotoxic (affect the cochlear system)
    2.  Vestibulotoxic (affect the vestibular system)

Ototoxic drugs can cause temporary or permanent damage, but is usually irreversible.

Ototoxic effect usually depends on the amount of the drug that is used, the dosage amount and the number of times the drug is taken.

Method of delivery is also a factor:
    1.  Pills and capsules (slowest method, and least likely to be ototoxic)
    2.  Intramuscular injections(faster than pills and capsules)
    3.  Intravenous solutions (fastest method, most likely to be ototoxic)

Previous exposure to ototoxic drugs can make a patient more susceptible to other ototoxic drugs that may not be known to be ototoxic.

Commonly used drugs that have ototoxic effects:
    1.  Aminoglycoside antibiotics (usually used for tuberculosis, respiratory tract
                                           infections, urinary tract infections, meningitis, etc.)
    2.  Chemotherapy drugs (Cisplatin, may be most ototoxic)
    3.  Loop diuretics (used to increase water and electrolytes in the urine)
    4.  Anti-inflammatory drugs (tend to cause flat 20-40 dB bilateral HL, usually high
                                            pitched).
    5.  Alcohol, marijuana, and tobacco
    6.  Various solvents and heavy metals

Factors that affect ototoxicity:
    1.  Advanced age, extreme youth, and hereditary factors
    2.  Size and physical condition of the patient
    3.  Preexisting cochlear pathology

Important issues in monitoring ototoxicity
    1.  A baseline should be established prior to use of ototoxic drugs
    2.  Carefully monitor hearing, especially high frequencies
    3.  Only changes of 10 dB or more should be suspect of ototoxicity

Exposure to noise can aggravate the effects of ototoxicity.

(Information taken from Christa M., Ball State University Au.D program)