A cerumenolytic is an ear wax (

cerumen Earwax, also known by the medical term cerumen, is a brown, orange, red, yellowish or gray waxy substance secreted in the ear canal of humans and other mammals. It protects the skin of the human ear canal, assists in cleaning and lubrication, a ...

) softening agent. Common cerumenolytics such as

hydrogen peroxide Hydrogen peroxide is a chemical compound with the formula . In its pure form, it is a very pale blue liquid that is slightly more viscous than water. It is used as an oxidizer, bleaching agent, and antiseptic, usually as a dilute solution (3%� ...

and

hydrogen peroxide - urea Hydrogen peroxide - urea (also called Hyperol, artizone, urea hydrogen peroxide, and UHP) is a solid composed of equal amounts of hydrogen peroxide and urea. This compound is a white crystalline solid which dissolves in water to give free hydroge ...

are topical preparations used to facilitate the removal of ear wax. Their side effects tend to be mild, including ear discomfort, transient loss of hearing,

dizziness Dizziness is an imprecise term that can refer to a sense of disorientation in space, vertigo, or lightheadedness. It can also refer to disequilibrium or a non-specific feeling, such as giddiness or foolishness. Dizziness is a common medical c ...

, and local irritation.

Medical uses

Cerumenolytics are used to soften and break up ear wax. Using a cerumenolytic can reduce the need for flushing the ear with irrigants for wax removal. Additionally, cerumenolytics can also facilitate the manual removal of ear wax. Overall, all cerumenolytics are considered to be equivalent in efficacy. Cerumenolytics are administered directly into the ear, which is a form of

topical administration A topical medication is a medication that is applied to a particular place on or in the body. Most often topical medication means application to body surfaces such as the skin or mucous membranes to treat ailments via a large range of classes ...

that can be specified as "ototopical." Generally, the use of a cerumenolytic involves instilling several drops of the product into the affected ear once or twice daily for a treatment duration of 3 to 5 days. Each instillation is relatively quick (less than 5 minutes) and can be done either at home or in a clinical setting. However, like all ear wax treatments, the ear wax can reaccumulate in the ear after treatment, necessitating further treatment. Cerumenolytics are not recommended in children less than 3 years-old.

Available forms and classification

Cerumenolytics are available as topical preparations intended for installation into the ear. Cerumenolytics can be classified based upon the formulation of their constituents: water based, oil based, or neither. Army Spc Taryn Emery cleans the ear of an Iraqi child 061127-M-5585B-016

Army Spc Taryn Emery cleans the ear of an Iraqi child 061127-M-5585B-016

Contraindications

Cerumenolytics should not be used in ears that in which the

ear drum In the anatomy of humans and various other tetrapods, the eardrum, also called the tympanic membrane or myringa, is a thin, cone-shaped membrane that separates the external ear from the middle ear. Its function is to transmit sound from the air ...

has been perforated or is otherwise nonintact. Cerumenolytics should also be avoided in ears that are actively infected due to the lack of research in this area (i.e. people with

otitis externa Otitis externa, also called swimmer's ear, is inflammation of the ear canal. It often presents with ear pain, swelling of the ear canal, and occasionally decreased hearing. Typically there is pain with movement of the outer ear. A high fever is ...

, a type of ear infection).

Adverse effects

In general, cerumenolytics can cause ear discomfort, transient loss of hearing,

, and local irritation. Local reactions are least frequent with cerumenolytics that lack

organic chemicals In chemistry, organic compounds are generally any chemical compounds that contain carbon-hydrogen or carbon-carbon bonds. Due to carbon's ability to catenate (form chains with other carbon atoms), millions of organic compounds are known. The s ...

, such as a saline.

Overdose

Using the cerumenolytic hydrogen peroxide as an example, no adverse effects are expected with overdose of an otic administered preparation. The average middle ear volume is 0.4 mL, which limits otic accumulation in overdose. It is unlikely that an cerumenolytic administered into the ear would cause systemic toxicity in an overdose situation, due to the lack of systemic absorption resulting from minimal volume flow within the inner ear. However, again using hydrogen peroxide as an example, clinically relevant overdoses of cerumenolytics are possible if the drugs are administered by other routes (e.g. by mouth).

Pharmacology

The mechanism of action of cerumenolytics vary by the classification. Water-based cerumenolytics, including water itself, work by hydrating ear wax, fragmenting

corneocytes Corneocytes are terminally differentiated keratinocytes and compose most of the stratum corneum, the outermost layer of the epidermis. They are regularly replaced through desquamation and renewal from lower epidermal layers and are essential for ...

(a type of skin cell) within the ear wax itself. Cerumenolytics with peroxides release oxygen upon contact with the skin, inducing

effervescence Effervescence is the escape of gas from an aqueous solution and the foaming or fizzing that results from that release. The word effervescence is derived from the Latin verb ''fervere'' (to boil), preceded by the adverb ''ex''. It has the same lin ...

(bubbling) that mechanically fragments ear wax. Oil-based cerumenolytics provide lubrication to the ear wax, softening the surface without fragmenting the ear wax. The mechanism of action of non-water- and non-oil-based cerumenolytics is unknown. Using carbamide peroxide as an example, the pharmacokinetics of cerumenolytics are not well studied.

Veterinary use

Cerumenolytics are used to treat cerumen impaction in cats and dogs. The removal of cerumen is also an important step in the treatment of

otitis Otitis is a general term for inflammation or infection, inner ear infection, middle ear infection of the ear, in both humans and other animals. When infection is present, it may be viral or bacterial. When inflammation is present due to fluid buil ...

in small animals.{{Subscription required Veterinary cerumenolytics possess different potencies. Diocytl sodium sulfosuccinate (DOSS), dioctyl calcium sulfosuccinate, and urea or

carbamide peroxide Hydrogen peroxide - urea (also called Hyperol, artizone, urea hydrogen peroxide, and UHP) is a solid composed of equal amounts of hydrogen peroxide and urea. This compound is a white crystalline solid which dissolves in water to give free hydrogen ...

are considered to be potent veterinary cerumenolytics.

References

Drugs Ear procedures