That is really a broad subject and probably more than anyone would be able to do in this Forum. In general most ointments are occlusive products traditionally based upon Petrolatum in many cases. Generally you are looking at a W/O emulsion. Further complicating the fact would be that Athletes Foot products are generally Over-The-Counter (OTC) products.
I would suggest googling some sample Formulations first.
IHK, I guess it’s intended to be a drug, not cosmetic product. Honestly, I find it disputable to use the ointment form for feet treatment, since it has so greasy consistency and pretty uncomfortable on the feet. Athlete foot is a complex disease and it may include both fungal and bacterial infections. Try to make a formulation based on emulsion.
Right, I wasn’t reading that he necessarily wanted to make any disease claims.
Tea tree oil is most definitely effective as killing Trichophyton rubrum, one of the fungi that is responsible for athlete’s foot, which maybe could be put on the label? I’m not sure. There’s plenty of research to support it.
Micro, for OTCs, yep, I agree with you. Dietary supplements can make a lot of limited claims, though, as long as they’re not claiming to do anything structure/function-related to the human body. It would require finesse, but I think there is (maybe?) enough gray area that an argument could be made for making functional claims for single herbs used in topical application as long as the claims don’t try to alter the body itself. How about referring to tea tree oil as “antiseptic” as Dessert Essence does?
I’m really asking here-anyone else with experience in the neutraceutical/cosmetic drug area, please chime in, maybe start a new thread!
With Tea Tree Oil, you have to use a very large amount in order to equal the effectiveness of other commonly used antimicrobials - greater than 10%. And with the higher rate needed, you encounter formula cost issues and irritation issues when the product is applied to the skin. Plus you will have more issues with formula stability, etc, as the tea tree oil - in very high amounts - puts extra demands on the emulisifers.
I have researched antimicrobials quite a bit and the best one imho, is polyhexanide - PHMB.