Phenytoin cream normalizes neural over activity
Phenytoin cream normalizes neural over activity on the skin. It is increasingly recognized that in a number of poly neuropathic pain states there are signs of neurogenic inflammation. Pain is induced by a malign cascade triggered by nerve cells in the epidermis, the keratinocytes and immune competent cells.
- “It has been suggested that the skin as a whole may act as a polymodal nociceptor which undergoes functional changes in painful conditions.” 
Phenytoin cream is a newly developed cream by the Institute of Neuropathic Pain, and protected by 2 patents, filed on December 6th, 2016. The cream contains 5 or 10% Phenytoin and here we picture one of the mechanisms of action, via the keratinocyte.
In neurogenic inflammation, the population of keratinocytes in the skin are characterized by upregulated sodium channels. Phenytoin cream can inhibit sodium channels, not only in nerves, but also on keratinocytes:
In neurogenic inflammation, sodium channels are upregulated on keratinocytes:
After application of phenytoin cream, pain is decreased, due to amongst others, normalization of the output of the keratinocytes, as the sodium channels are blocked. Leading to clinical relevant pain reduction:
Succesful topical treatment
Keratinocytes have been identified as key players in the peripheral up regulation of pain. By topical treatment using sodium channel blockers, such as phenytoin, pain can be reduced.
In our hands pain reduction in neuropathic pain states characterized by neurogenic inflammatory factors (SFN, diabetic neuropathy, CIAP, herpes zoster, chemo-induced PNP ), pain can be reduced within 20-30 minutes.
Phenytoin cream has been developed in 2 concentrations: 5 % and 10%. Phenytoin is an 80-years old molecule, but again and again with new applications in medicine. We have as first research group worldwide identified phenytoin cream as a potent analgesic cream.
January 2017, Jan M. Keppel Hesselink, MD, PhD
‘Phenytoin cream normalizes neural over activity’
Watch here our video’s about Phenytoni cream.
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