RE: Re: Transdermal cream bases--a study of absorption

[Guest guest]

Hi Virginia,

My base is Medisca HRT. Do you know how this compares to Versabase?

Thanks!

Liz

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www.ojaipaintedminis.com

From: rhythmicliving [mailto:rhythmicliving ] On Behalf Of Virginia SpeaksSent: Wednesday, March 05, 2008 10:10 AMTo: rhythmicliving Subject: Re: Transdermal cream bases--a study of absorption

Off-group I was sent a question about VersaBase v. Lipoderm--their relative penetrating ability. According to PCCA, Lipoderm should be used to take medications through the lipophilic system into the cells (such as into joints). Hormones just need to get into the bloodstream, so VersaBase is the best base for them. If I understood the PCCA consultant correctly, he said that hormones are already lipophilic. Also a comment was made about these penetration studies using male cadavers. The consultant said that the skin samples of male and female are no different. Virginia> >> > I'm now back working at a compounding pharmacy (doing marketing of > > compounds), and I've discovered that PCCA (Pharmaceutical Compounding > > Centers of America, which supplies a lot of compounders with their > > chemicals and bases) did a study of the percutaneous absorption of > > progesterone, in vitro, using human cadaver skin abtained within 24-> > 48 after death. (The actual study was performed by PRACS Institute, > > an independent research facility.) The four base creams tested were > > VersaBase Cream, Cosmetic HRT, a mixture of VersaBase Cream (95%) and > > VersaBase Gel (5%), and Vanicream. (The first three bases are PCCA > > bases; Vanicream is from Pharmceutical Specialties, Inc.) The > > progesterone was Progesterone USP, PCCA Special Micronized, 50 mg/gm. > > The creams were tested on replicate sections from three different > > cadaver skin donors for absorption over a 48-hour period. The skin > > was mounted in specially designed diffusion cells that allowed it to > > be maintained at a temperature and humidity to match typical in vivo > > conditions. The progesterone was not rubbed into the skin but applied > > with a pipette and left to diffuse.> > > > Results: all the bases demonstrated the ability to transport > > progesterone across human skin in vitro. When comparing the bases' > > ability to transport progesterone deep into the dermis, PCCA > > VersaBase Cream out-performed all bases, delivering more than four > > times as much progesterone as VaniCream. Looking at the graph > > included in the study, the other two bases delivered a little less > > than half of the amount delivered by VersaBase. Absorption was > > observed to rise to a peak at approximately seven hours after > > application followed by a slow decline in flux over time and what the > > study called a "transient secondary peak" of penetration at > > approximately 28 hours after application at about half the flux seen > > at the maximum.> > > > My pharmacy is switching to VersaBase, so I guess I'll be paying some > > attention to whether my hormone dosages need to be lowered in the > > near future. Others using transdermal creams may want to check with > > their pharmacist to see what base he/she uses. It could be a reason > > why some experience good results with transdermal creams and others > > do not.> > > > Virginia> >>