Benzocaine is a local anesthetic commonly used as a topical pain reliever orin cough drops. It is the active ingredient in many over-the-counter anestheticointments such as products for oral ulcers. It is also combined with antipyrineto form A/B otic drops to relieve ear pain and remove earwax.
Benzocaine is the ethyl ester of p-aminobenzoicacid (PABA). It can be prepared from PABA and ethanol by Fischer esterificationor via the reduction of ethyl p-nitrobenzoate. Benzocaine is sparingly solublein water; it is more soluble in dilute acids and very soluble in ethanol,chloroform and ethyl ether. The melting point of benzocaine is 88–90 °C, and the boiling point is about 310 °C. The density of benzocaine is 1.17 g/cm3.
Benzocaine is used as a key ingredient innumerous pharmaceuticals:
Some glycerol-based ear medications for usein removing excess wax as well as relieving ear conditions such as otitis mediaand swimmers ear.
Some previous diet products such as Ayds.
Some condoms designed to prevent prematureejaculation. Benzocaine largely inhibits sensitivity on the penis, and canallow for an erection to be maintained longer (in a continuous act) by delayingejaculation. Conversely, an erection will also fade faster if stimulus isinterrupted.
Benzocaine mucoadhesive patches have beenused in reducing orthodontic pain.
In Poland it is included, together withmenthol and zinc oxide, in the liquid powder (not to be confused with theliquid face powder) used mainly after mosquito stings. Today's ready madePudroderm was once used there as pharmaceutical compound.
