Antipyrine and Benzocaine (Otic)

INN:
Antipyrine—Phenazone. ^{01}

BAN:
Antipyrine—Phenazone. ^{01}


JAN:
Benzocaine—Ethyl aminobenzoate. ^{01}

VA CLASSIFICATION
Primary: OT400
Secondary: OT300

Commonly used brand name(s): A/B Otic; Allergen; Analgesic Otic; Antiben; Auralgan; Aurodex; Auroto; Dolotic; Ear Drops; Earache Drops; Otocalm.

Note: For a listing of dosage forms and brand names by country availability, see Dosage Forms section(s).



Category:


Analgesic-anesthetic (otic)—

cerumen removal adjunct—

Indications

Unaccepted
Antipyrine and benzocaine otic combination has been used to relieve pain and inflammation in the congestive and serous stages of acute otitis media ^{{02} {03} {12} {13}} and to facilitate removal of cerumen from the wall of the ear canal. ^{{02} {12}} However, it is no longer recommended for these purposes, ^{{06} {07}} because of questionable effectiveness and because benzocaine frequently causes contact dermatitis.


Pharmacology/Pharmacokinetics

Physicochemical characteristics:

Chemical group—
    Antipyrine: A pyrazolone derivative. ^{05}
    Benzocaine: An aminobenzoic acid (para-aminobenzoic acid; PABA) derivative. ^{01}
Molecular weight—
    Antipyrine: 188.23 ^{01}
    Benzocaine: 165.19 ^{01}
    Glycerin: 92.09 ^{01}

Mechanism of action/Effect:

Both antipyrine and benzocaine are employed for their analgesic/local anesthetic effects. ^{02} The anhydrous glycerin vehicle is hygroscopic and may provide a decongestant action. ^{02}


Precautions to Consider

Cross-sensitivity and/or related problems

Patients sensitive to benzocaine or other ester-derivative anesthetics may be sensitive to this medication also. ^{01}

Carcinogenicity/Mutagenicity

Studies have not been done. ^{{02} {12}}

Pregnancy/Reproduction

Pregnancy—
Studies in humans have not been done. However, problems have not been documented. ^{{02} {12}}

Studies in animals have not been done. ^{{02} {12}}

FDA Pregnancy Category C. ^{{02} {12}}

Breast-feeding

It is not known whether this medication is distributed into breast milk. ^{{02} {12}} However, problems in humans have not been documented.

Pediatrics

The risk of benzocaine-induced methemoglobinemia may be increased in infants, ^{05} especially infants up to 3 months of age. However, pediatrics-specific problems that would limit the usefulness of antipyrine and benzocaine combination in older children are not expected.


Geriatrics


Appropriate studies on the relationship of age to the effects of antipyrine and benzocaine combination have not been performed in the geriatric population. However, no geriatrics-specific problems have been documented to date.

Medical considerations/Contraindications
The medical considerations/contraindications included have been selected on the basis of their potential clinical significance (reasons given in parentheses where appropriate)— not necessarily inclusive (» = major clinical significance).


Risk-benefit should be considered when the following medical problems exist
Sensitivity to antipyrine or benzocaine^{02}{03}
Spontaneous perforation of or drainage through the eardrum membrane^{02}{12}    (increased risk of otorrhea and irritation)




Side/Adverse Effects
The following side/adverse effects have been selected on the basis of their potential clinical significance (possible signs and symptoms in parentheses where appropriate)—not necessarily inclusive:

Those indicating need for medical attention only if they continue or are bothersome
    
Allergic reaction, local^{05} (itching, burning, redness, or oozing sores in the ear)




Patient Consultation
As an aid to patient consultation, refer to Advice for the Patient, Antipyrine and Benzocaine (Otic).

In providing consultation, consider emphasizing the following selected information (» = major clinical significance):

Before using this medication
»   Conditions affecting use, especially:
Sensitivity to benzocaine or antipyrine





Use in children—Risk of methemoglobinemia in infants


Proper use of this medication

Proper administration technique
May warm medication to body temperature (37 °C or 98.6 °F) by holding bottle in hand for a few minutes before using

Slowly fill ear canal while lying on side or tilting head with affected ear facing up ^{{22} {23} {24}}

Keep ear facing up for 5 minutes or, for patients who cannot stay still that long, for at least 1 or 2 minutes ^{{22} {23} {24}}

A cotton plug moistened with medication may be gently placed at the ear opening for no longer than 5 to 10 minutes ^{{22} {23} {24}} to ensure retention

For cerumen removal, the ear canal should be irrigated with warm water after the medication has been used for 2 or 3 days ^{08}
Preventing contamination of ear drops by not touching dropper to any surface including ear

» Not rinsing dropper after use; keeping container tightly closed

Missed dose
Using as soon as possible; not using if almost time for next dose

» Proper dosing

» Proper storage


Side/adverse effects
Discontinuing treatment if signs and symptoms of local allergic reaction occur


General Dosing Information
This medication may be warmed to body temperature (37 °C or 98.6 °F) by holding the bottle in the hand for a few minutes prior to using. ^{03}

The medication should be instilled with the affected ear facing up. Several minutes after the medication has been instilled the patient should gently place a cotton plug moistened with a little medication at the ear opening for no longer than 5 to 10 minutes ^{{22} {23} {24}} to ensure retention. ^{02}

When the medication is used to facilitate removal of cerumen, the ear canal should be irrigated with warm water, preferably by the physician, ^{08} after the medication has been used for 2 or 3 days. ^{02}

Treatment should be discontinued immediately if any sign of hypersensitivity or irritation occurs. ^{{02} {12}}


Otic Dosage Forms

ANTIPYRINE AND BENZOCAINE OTIC SOLUTION USP

Usual adult and adolescent dose
Analgesic-anesthetic, otic
Topical, to the ear canal, a sufficient quantity to fill the ear canal every one to two hours until relief is obtained. ^{{02} {12}}

Cerumen removal adjunct¹
Topical, to the ear canal, a sufficient quantity to fill the ear canal three times a day for two or three days. ^{12} After two or three days the ear canal should be irrigated with warm water. ^{02}


Usual pediatric dose
See Usual adult and adolescent dose.

Strength(s) usually available
U.S.—


54 mg of antipyrine and 14 mg of benzocaine, dissolved in anhydrous glycerin to make 1 mL (Rx) [A/B Otic^{15}{18}] [Allergen^{09}{14}] [Analgesic Otic^{15}{16} (oxyquinoline sulfate)] [Antiben^{15}{19}] [Auralgan^{12} (oxyquinoline sulfate)] [Aurodex^{15}{20}] [Auroto^{09}{10} (oxyquinoline sulfate)] [Dolotic^{15}{21}] [Ear Drops^{09}{14} (oxyquinoline sulfate)] [Otocalm^{09}{15}][Generic]^{09}{11}

Canada—


54 mg of antipyrine and 14 mg of benzocaine, dissolved in anhydrous glycerin to make 1 mL (OTC) [Auralgan^{13}]


90 mg of antipyrine and 14 mg of benzocaine, dissolved in anhydrous glycerin to make 1 mL (OTC) [Earache Drops^{17}]

Packaging and storage:
Store below 40 °C (104 °F), preferably between 15 and 30 °C (59 and 86 °F), unless otherwise specified by manufacturer. Store in a tight, light-resistant container. Protect from freezing.

Note: The solution congeals at 0 °C (32 °F) but returns to liquid state at room temperature. Therapeutic qualities are not affected. ^{02}


Auxiliary labeling:
   • For the ear.
   • Keep container tightly closed.

¹ Not included in Canadian product labeling.

Revised: 07/14/1995

References

1. Fleeger CA, editor. USAN 1994. USAN and the USP dictionary of drug names. Rockville, MD: The United States Pharmacopeial Convention, Inc., 1993: 53, 79, 312.
   

2. Auralgan (Wyeth-Ayerst). In: PDR Physicians' desk reference. 47th ed. 1993. Montvale, NJ: Medical Economics Data, 1993: 2548-9.
   

3. Auralgan (Ayerst). In: Krogh CME, editor. CPS Compendium of pharmaceuticals and specialties. 28th ed. Ottawa: Canadian Pharmaceutical Association, 1993: 118.
   

4. Open.
   

5. Krogh CME, editor. CMS Canadian self-medication. 4th ed. Ottawa: Canadian Pharmaceutical Association, 1992: I 156-7; II T49.
   

6. Drug evaluations subscription. Chicago: American Medical Association, Fall 1992: III 1:14.
   

7. Panel consensus, draft 10/93.
   

8. Panelist comment, draft 10/93.
   

9. Olin BR, editor. Drug facts and comparisons. St. Louis: Facts and Comparisons Inc, 1992 November: 519.
   

10. Auroto package insert (Barre-National—US), Rev 7/93, Rec 10/94.
    

11. Red book 1994. Montvale, NJ: Medical Economics Data, 1994. August 1994 Update: 9.
    

12. Auralgan (Wyeth-Ayerst). In: PDR Physicians' desk reference. 49th ed. 1995. Montvale, NJ: Medical Economics Data Production Company, 1995: 2649.
    

13. Auralgan (Whitehall-Robins). In: Krogh CME, editor. CPS Compendium of pharmaceuticals and specialties. 29th ed. Ottawa: Canadian Pharmaceutical Association, 1994: 127.
    

14. Red book 1994. Montvale, NJ: Medical Economics Data, 1994. August 1994 Update: 6, 21.
    

15. Red book 1994. Montvale, NJ: Medical Economics Data, 1994: 85, 104, 105, 110, 176, 305.
    

16. Analgesic Otic package insert (Akorn—US), Rev 6/93, Rec 9/94.
    

17. Personal communication, Peter Grasman, Regal division of Bradcan—Canada, 9/19/94.
    

18. Personal communication, Clay-Park—US, 9/16/94.
    

19. Personal communication, Hi-Teck—US, 9/16/94.
    

20. Personal communication, Major—US, 9/16/94.
    

21. Personal communication, Marlop—US, 9/16/94.
    

22. Reviewers' responses to Family Practice Advisory Panel Memos #35, 41, and 43 of 10/27/94, 1/11/95, and 2/21/95, respectively.
    

23. Reviewers' responses to Otorhinolaryngology Advisory Panel Memos #6, 7, and 8 of 10/27/94, 1/11/95, and 2/21/95, respectively.
    

24. Reviewers' responses to Pediatrics Advisory Panel Memos #34, 39, and 42 of 11/16/94, 1/11/95, and 2/21/95, respectively.