CalciuDobesilate as an Earwax Solvent

Calcium Dobesilate as a Wax Solvent

Author: Vaidya, Sudhakar - Associate Professor, Otolaryngology, RD Gardi Medical College, Ujjain, MP India

Institution: RD Gardi Medical College, Ujjain MP (India)

Abstract: Several studies have assessed the effectiveness of softening the cerumen with agents like olive oil, sodium bicarbonate, docusate sodium, para-dichlorobenzene, hydrogen peroxide, and triethanolamine polypeptide. In this study, a randomized controlled double blind- study evaluated a new earwax solvent Calcium dobesilate (a venotonic drug). CALCIUM DOBESILATE ear drops were found to clear the ear canal of wax in 92.5% as compared to 26.7% using paracholrodiabenenze (p<0.001) and 7.1% using normal saline (p<0.001). Calcium dobesilate also had a minimal of discomfort and devoid of any hazard in comparison to paracholrodiabenenze.

Introduction: Earwax (Cerumen) is produced in the cartilaginous portion of the external auditory canal. It is composed of wax, oil, water, desquamated skin, and dirt. The wax component is a mixture of secretions of varying viscosity produced by both sebaceous and modified apocrine sweat glands. The major components of cerumen are the end products of the HMG-CoA reductase pathway and include: Cholesterol, lanosterol and squalene.¹The appearance and consistency of earwax varies widely depending upon the relative amount of each of its components.²

Cerumen provides varying amounts of protection against bacteria^3,4,5, fungi⁶, and insects. Earwax also assists in lubrication and cleaning. A useful substance but it can be menacing, causing discomfort and disease. Excess or impacted cerumen can press against the eardrum and/or block the external auditory canal resulting in impaired hearing. The consistency and hardness is an important factor, because harder cerumen is more likely to accumulate, although, it does not need removal unless the patient has a specific complaint related to impacted wax.

Impacted wax sometimes creates very tenacious, tedious and troublesome symptoms. An abnormally shaped ear canal, overproduction of earwax by the glands in the ear canal, wax thrusted against the eardrum by cotton-tipped applicators, hair pins, or other objects that people put in their ears or trapped against the eardrum by a hearing aid are some of the factors which predisposes to impacted wax.

A wide spectrum of symptoms seen in situations of impacted wax, ranging from an asymptomatic condition to causing a hearing impairment. Diminished auditory perception may be associated with itching in the external auditory canal, noise or ringing in the ears, sensation of fullness or heaviness in the ear, irritation, itching pain, tinnitus, dizziness, or vertigo.^7,8 It can not only be bothersome to the patient but also to consulting physician because it produces a dilemma. A wax impaction deters and delays the adequate examination of the tympanic membrane, without which a proper diagnosis of ear disease can not be made.

Manual syringing has been historically the most common method of cleaning the earwax, but can cause perforation of the eardrum and other complications, such as bleeding and otitis externa.⁹ Proprietary wax softeners can be categorized into water-based or oil-based solutions. Neither type of solution demonstrates any major advantages of one preparation over another. Whichever of the preparations are used, several days of treatment are required to achieve clearance rates of up to 40%.¹⁰ Proprietary oil base wax softener have arachis oil/turpentine oil, chlorbutol or p-dichlorobenzene, while water based preparations contain sodium bicarbonate, glycerol or sterile water. Use of liquid paraffin, or a ceruminolytic agent with a mechanical extraction by curette or irrigation, or a combination of the above methods may carry the risk of patient discomfort, trauma to tympanic membrane and middle ear, and infection of external auditory canal and middle ear.

McAuley, DF², reviewed several studies on the effectiveness of cerumen softening "with agents such as olive oil, sodium bicarbonate, docusate sodium, para-dichlorobenzene, hydrogen peroxide, and triethanolamine polypeptide." He reported that many of these studies were uncontrolled with a small number of subjects.

Objective: To determine the safety and preliminary effectiveness of a single application of 20 mg per milliliter ear solution of Calcium dobesilate for cerumen impaction of human ear.

Molicular Formula of Calcium Dobesilate
Figure 1: Molecular Formula of Calcium dobesilate

Material and methods: In the present study, a total of 98 adult and pediatric patients with bilateral earwax impactions from the ENT department of RD Gardi Medical College were enrolled randomly into this study. The age of the patients ranged from 1.5 to 65 years, 26% were less than 5 years of age, 35% were female and 65% were male. The study was conducted over an eight month period, between August 2006 and September 2007. An ENT surgeon determined the presence of ear canal obstruction or impaired visualization of the eardrum requiring removal of earwax. Both the ENT surgeon and the nurse were blinded as to which clinical arm the patients were enrolled in. To mask the treatments, doses were placed in the same type of opaque bottles to obscure the color difference. The enrollment code was broken on the completion of the study to which of the agents were used in the study's patients.

A 1-mL dose of either paracholrodiabenenze (p-DCB) or Calcium dobesilate (20mg/ml) or normal saline was placed in the affected ear canal and allowed to remain for 20 minutes. The liquefied wax was removed with a cotton-tipped Jobson-Horne probe. If the wax could not be removed, the ear was carefully irrigated with 50 ml. sterile water.

Ear Wax Solvents
Figure 2: Substances Used in 98 Patients with Bilateral Wax Impactions

The exclusion criteria were as follows:

1. Traumatic or known perforation

2. Possible or suspected perforation

3. Overt ear infection.

4. Absence of wax in canal

5. Lack of cooperation

Effectiveness endpoints are defined as complete removal of wax from the external auditory canal along with complete visualization of TM. Safety endpoints include any irritation or local allergic reaction to the agent used and discomfort to the patient.

Results: Different substances used in a total of 98 patients (196 ears) were, 40 (80 ears) received Calcium dobesilate, 30 (60 ears). Paracholrodiabenenze (p-DCB) and 28 (56 ears) normal saline. Experimental groups were similar in age, race, sex, earwax consistency, and degree of obstruction. Complete clearing was achieved in 92.5% of the Calcium dobesilate -treated patients and 26% of the paracholrodiabenenze -treated patients (p<0.0001). No adverse reactions were reported. Calcium dobesilate significantly improved the proportion of tympanic membranes that were completely visualized versus application of the saline or p-DCB. No syringing was required with any of the cases with Calcium dobesilate.

Comparison of Ear Wax Solvents
Figure 3: Comparative Results of Two Ear Solvents and the Control (Red: Total Ears; Blue: Wax Cleared).

Discussion: Calcium dobesilate (C6H5O5S)2.Ca;C12H10Ca2O10S2, Molecular Weight :418.41) is an orally administered angioprotective agent which promotes venous blood flow and is widely prescribed in more than 60 countries.¹¹ Calcium dobesilate has three main indications: chronic venous disease, diabetic retinopathy and the symptoms of hemorrhoids, although its mechanism of action is not yet fully understood.^11,12,13 It has also been studied in the treatment of plaque psoriasis with good results. Exact mechanism of the ceruminolytic action is not known¹³. For softening of cerumen, Calcium dobesilate shows very promising results with minimal of discomfort and devoid of reactions in comparison to paracholrodiabenenze (p-DCB).

Efficacy of Solvents Used to Remove Earwax
Figure 3: Chi Square Analysis of Efficacy of Two Earwax Solvents and Saline Control in Earwax Removal

Video of in vitro application of Calcium dobesilate under a microscope over earwax collected from the ear canal.

Conclusion:

1. Calcium dobesilate significantly improved the proportion of tympanic membranes that were completely visualized versus application of the saline or p-dichlorobenzene.

2. No syringing was required with any of the cases with Calcium dobesilate.

3. If one application was not effective, instill 1ml of 20mg/mL Calcium dobesilate again for 10 min before another attempt.

4. Other wax solvents required regular use for 3 to 10 days for complete removal of wax from the ear.

5. Calcium dobesilate represents a very cost effective alternative to facilitate the removal of cerumen, although more studies are needed to determine the best approach to treatment. Available evidence supports the use of a cerumunolytic over multiple irrigations in order to help reduce potential complications such as perforation, canal trauma, pain, tinnitus, vertigo, or otitis media. However, Calcium dobesilate should be avoided if the status of the tympanic membrane is unknown.

6. It is quantitatively superior to paracholrodiabenenze and placebo for acute earwax removal in the office. This study was not designed to evaluate the efficacy of ceruminolytics on a chronic basis. Clinicians should use it dissolved in sterile water.

Recommendations for Clinical Practice

Use of an effective cerumunolytic over multiple irrigations reduces potential complications such as perforation, canal trauma, pain, tinnitus, vertigo, or otitis media. ¹⁴
Calcium dobesilate should be avoided if the status of the tympanic membrane is unknown.

Acknowledgment: Authors are grateful to Dr. V K. Mahadik, Medical Director, R.D. Gardi Medical College & Ujjain Charitable Trust Hospital Ujjain (MP) for giving us permission to publish this research paper and for encouragement and support.

Address for correspondence
Dr. Sudhakar Vaidya, Associate. Professor
Dept. of Otorhinolaryngology
R D Gardi Medical College & Ujjain Charitable Hospital
D-3/2 ,Saupan ,Dhanvatari Nagar ,Near Birla Hosp. UJJAIN (MP), India
Email : [drsvaidya@hotmail.com]

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