Your Compounding Questions Answered
Author: Martin A. Erickson III, RPh
Mr. Erickson is director of professional affairs at Gallipot Inc.
Q:I received a request to make a salicylic acid 60% in Plastibase topical prep. I believe the intention is for application to warts. Do you happen to have a recipe for this topical product?
A: Salicylic acid has been used as a treatment for warts. The salicylic acid is a keratolytic. In this concentration, it can damage the surrounding skin quickly; suggest a protective cover over healthy tissue to avoid burning and sloughing. This concentration also will produce a relatively inelegant, gritty preparation, but the formulation can be compounded. A small amount of ethanol 200 proof will help you incorporate the salicylic acid into the vehicle. Plastibase (Jelene, Gallipot) it may present some incompatibility with high salicylic acid concentration (the material may begin to “weep,” or exude liquid, because the vehicle is a combination of polyethylene and mineral oil). A better choice for the vehicle might be hydrophilic petrolatum, because it will provide an occlusive dressing (which could make a lower concentration of salicylic acid more effective).
Salicylic acid 60% Topical Ointment or Gel
Salicylic acid 60% (crystalline powder)
Alcohol (ethanol) qs
Plastibase or Jelene qs ad 100% (or substitute hydrophilic petrolatum)
1. Weigh/measure ingredients accurately.
2. Place the salicylic acid in a ceramic or Wedgwood mortar and finely pulverize the material with the pestle.
3. Add a small amount of alcohol to the mortar in and triturate to form a paste.
4. If hydrophilic petrolatum is chosen as the vehicle, soften (do not melt) it, and use geometric trituration technique to combine with the vehicle. If Plastibase or Jelene is chosen as the vehicle, do not soften the vehicle; use geometric spatulation technique to combine the salicylic acid paste with the vehicle.
5. Suggest protective dressing over healthy tissue around the wart before application of the preparation. ■
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