Usage
Benzocaine + Chlorbutol ear drops are primarily prescribed for impacted earwax (cerumen) and keratosis obturans (accumulation of keratin debris in the ear canal). It’s classified as an otic agent. More specifically, it combines a local anesthetic (benzocaine), antiseptic (chlorbutol), and cerumenolytics (paradichlorobenzene and turpentine oil) to soften earwax, reduce pain, and prevent infection.
Alternate Names
This combination is often referred to as Benzocaine and Chlorbutol Ear Drops or Paradichlorobenzene + Benzocaine + Chlorbutol + Turpentine Oil Ear Drops. Some brand names include Otiflox WX, EDVAAR W, Ceruklin, and Audisol. A/B Otic drops are also sometimes used, although they refer to only Antipyrine and Benzocaine without the Chlorbutol. Many other brand names exist.
How It Works
Pharmacodynamics:
- Benzocaine: A local anesthetic that blocks voltage-gated sodium channels in nerve membranes, inhibiting nerve impulse transmission and reducing pain sensation.
- Chlorbutol: Acts as a preservative with mild antiseptic and local anesthetic properties.
- Paradichlorobenzene: Softens and dissolves earwax by disrupting its structure.
- Turpentine Oil: Acts as a solvent and lubricant, facilitating wax removal. It may also have anti-inflammatory and antiseptic properties.
Pharmacokinetics: Primarily topical action within the ear canal. Systemic absorption is minimal, but individual ingredients undergo different metabolic and excretion pathways.
Mechanism of Action: Each drug in the formulation works by itself. There is no synergistic effect, there are independent effects at the site of topical application.
Elimination Pathways: Since systemic absorption is limited, excretion primarily occurs through the ear canal as softened earwax. Systemic routes such as urine and feces are not primary routes of elimination.
Dosage
Standard Dosage
Adults: 2-3 drops into the affected ear, 2-3 times daily. Treatment duration varies depending on the severity of impaction.
Children: Use in children under 12, and especially under 1 year old, is generally not recommended without consulting a healthcare professional. If used in children, please use under close medical supervision. Use in infants and small children should not happen without a consultation with a qualified physician.
Special Cases:
- Elderly Patients: Use with caution.
- Patients with Renal Impairment: Use with caution.
- Patients with Hepatic Dysfunction: Use with caution.
- Patients with Comorbid Conditions: Use with caution in patients with hearing problems, intestinal problems, kidney problems, myasthenia gravis, and Parkinson’s disease.
Clinical Use Cases
The primary clinical use is for impacted earwax and keratosis obturans. It is not typically used for intubation, surgical procedures, mechanical ventilation, ICU use, or emergency situations.
Dosage Adjustments
Dosage adjustments are generally not required, but caution is advised in patients with pre-existing conditions, especially those affecting the ear, kidney, or liver.
Side Effects
Common Side Effects:
- Temporary stinging or burning sensation in the ear
- Itching or redness in or around the ear
- Unpleasant taste in the mouth (if the drops flow into the mouth)
Rare but Serious Side Effects:
- Allergic reactions (anaphylaxis: wheezing, fast heart rate, clammy skin, light-headedness, breathing difficulties)
- Methemoglobinemia (rare but serious blood disorder)
- Angioedema (swelling beneath the skin)
Long-Term Effects:
No significant long-term effects are expected with short-term use. Prolonged use may increase the risk of local irritation or sensitization.
Contraindications
- Known hypersensitivity to any of the ingredients (benzocaine, chlorbutol, paradichlorobenzene, or turpentine oil)
- Perforated eardrum
- Inflamed ear canal
- Eczema on the outer ear
Drug Interactions
No specific drug interactions have been noted. However, always inform your doctor about all medications you are taking to prevent any potential interactions.
Pregnancy and Breastfeeding
Consult your doctor before using this medication if you are pregnant, planning to become pregnant, or breastfeeding. Safety in these situations is not well established.
Drug Profile Summary
- Mechanism of Action: Combined local anesthetic, antiseptic, and cerumenolytic action.
- Side Effects: Stinging, burning, itching, redness, unpleasant taste, rare allergic reactions.
- Contraindications: Hypersensitivity, perforated eardrum, inflamed ear canal, eczema on the outer ear.
- Drug Interactions: No specific interactions noted.
- Pregnancy & Breastfeeding: Consult a doctor before use.
- Dosage: 2-3 drops in affected ear, 2-3 times daily (adults). Not recommended for children under 12 without medical advice, and specifically under 1 year old.
- Monitoring Parameters: Observe for local reactions, allergic symptoms, or worsening ear conditions.
Popular Combinations
This combination itself is the common formulation. Individual components may be combined with other drugs for different indications.
Precautions
- Do not insert the dropper too deep into the ear canal.
- Avoid contact with eyes, nose, and mouth.
- If accidental contact occurs, rinse thoroughly with water.
- Discontinue use if irritation or allergic reaction occurs.
FAQs (Frequently Asked Questions)
Q1: What is the recommended dosage for Benzocaine + Chlorbutol ear drops?
A: For adults, instill 2-3 drops into the affected ear, 2-3 times daily. Not recommended for children under 12 without medical advice, and specifically under 1 year old.
Q2: How long does it take for this medication to work?
A: The onset of pain relief from benzocaine is rapid. Earwax softening may take a few days, depending on the impaction.
Q3: Can I use these drops if I have a perforated eardrum?
A: No, this medication is contraindicated in patients with a perforated eardrum.
Q4: What should I do if I experience burning or stinging after using the drops?
A: Mild, temporary stinging or burning may occur. If it is severe or persistent, discontinue use and consult your doctor.
Q5: Can I use these drops if I have an ear infection?
A: While chlorbutol has mild antiseptic properties, these drops are primarily for wax removal. Consult your doctor if you suspect an ear infection. They can determine if they are suitable or if other treatment is necessary.
Q6: Can I use this medication while pregnant or breastfeeding?
A: Consult your doctor before using this medication if you are pregnant, breastfeeding, or planning to become pregnant, as the safety in these situations is not well established.
Q7: What should I do if I accidentally swallow some of the ear drops?
A: Systemic absorption is minimal with topical application. If ingested, contact your doctor or local poison control center, especially for a child who has ingested these drops.
Q8: How should I store this medication?
A: Store in a cool, dry place away from direct sunlight and heat.
Q9: Can I use these drops with other ear medications?
A: Inform your doctor about all medications you are using, including other ear drops, to avoid potential interactions. Generally avoid using multiple ear drops together.
