The dorsal root ganglia, however, are located outside of the blood-brain barrier making them more susceptible.Pyridoxine is converted to pyridoxal phosphate via two enzymes, pyridoxal kinase and pyridoxine 5′-phosphate oxidase. High levels of pyridoxine can inhibit these enzymes. As pyridoxal phosphate is the active form of vitamin B6, this saturation of pyridoxine could mimic a deficiency of vitamin B6. Tolerable upper limits
Several government agencies have reviewed the data on vitamin B6 supplementation and produced consumption upper limits with the desired goal to prevent sensory neuropathy from excessive amounts. Each agency developed its own criteria for usable studies in relation to tolerable upper limits, and as such the recommendations vary by agency. Between agencies, current tolerable upper limit guidelines vary from 10 mg per day to 100 mg per day. Reviews of vitamin B6 related neuropathy cautioned that supplementation at doses greater than 50 mg per day for extended periods of time may be harmful and should be discouraged. In 2008, the Australian Complementary Medicines Evaluation Committee recommended warning statements appear on products containing daily doses of 50 mg or more vitamin B6 to avoid toxicity.The relationship between the amount of vitamin B6 consumed, and serum the levels of those who consume it, varies between individuals. Some people may have high serum concentrations without symptoms of neuropathy. It is not known if inhalation of vitamin B6 while, for example, working with animal feed containing vitamin B6 is safe.
Since the latter salt is unusual in the pharmacopeia, the manufacturer increased the amount of oxycodone hydrochloride to 4.8355 mg and discontinued the oxycodone terephthalate. Miscellaneous
The combination oxycodone/aspirin is also sold under the brand name Endodan. All products containing oxycodone (including Percodan, Percocet, OxyContin) have the potential to be habit-forming. Oxycodone can produce drug dependence of the morphine type and, therefore, has the potential for being addictive. See also
Embeda
Hypnorm
Percocet
Targin
Vicodin
Vicoprofen

References
External links
Percodan Prescribing Information from Endo Pharmaceuticals. Search "Percodan" in FDA Archives; shows approval in 1950.