Is loss of response to melatonin treatment associated with slow melatonin metabolism?
We hypothesise that loss of response to melatonin treatment can be caused by slow metabolisation of exogenous melatonin. As melatonin is metabolised in the liver almost exclusively by cytochrome P450 enzyme CYP1A2, this slow melatonin metabolism is probably due to decreased activity/inducibility of CYP1A2. In patients with loss of response to melatonin, a melatonin clearance test should be considered and a considerably dose reduction is advised.
Anti-CCP antibodies and the HLA-DRB1 (70)DERAA(74) sequence influence the age at onset of RA.