Posted by Brainbeard on April 23, 2011, at 6:18:43
I'm experimenting with both options, and have come to some preliminary conclusions. First, let's have a look at this table, showing the pharmacokinetic profile of immediate-release methylphenidate (twice/day) compared with that of the branded and generic sustained-release products (Ritalin immediate release has the little greyish squares and has the highest peaks - hang on, it's a looong web address): http://www.google.nl/imgres?imgurl=http://img.medscape.com/fullsize/migrated/462/703/pharm462703.fig5.gif&imgrefurl=http://www.medscape.com/viewarticle/462703_5&usg=__edIz6njlhSxqSPHFqJtfFLNVZPU=&h=363&w=491&sz=17&hl=nl&start=0&zoom=1&tbnid=tgYVCMkfDaxmvM:&tbnh=118&tbnw=159&ei=TfexTb6_KcjpOdSeuf4I&prev=/search%3Fq%3DPharmacokinetic%2Bprofile%2Bof%2Bimmediate-release%2Bmethylphenidate%2B(twice/day)%2Bcompared%2Bwith%2Bthat%2Bof%2Bthe%2Bbranded%2Band%2Bgeneric%2Bsustained-release%2Bproducts.%26um%3D1%26hl%3Dnl%26sa%3DN%26biw%3D1111%26bih%3D538%26tbm%3Disch&um=1&itbs=1&iact=hc&vpx=115&vpy=71&dur=2326&hovh=193&hovw=261&tx=182&ty=81&page=1&ndsp=18&ved=1t:429,r:0,s:0.
This table shows that Ritalin, i.e. methylphenidate instant release, has blood levels peak up to the second hour, after which they steeply decline. It's around the two hour-mark that I begin to lose the benefits of the drug; this apparently correlates with blood levels beginning to decline.
Now, I experience the same twist of fate on Concerta, after about eight hours, whereas the drug is supposed to cover a twelve-hour time-span. But have a look at this table, where Concerta's pharmacokinetic profile is shown: http://www.google.nl/imgres?imgurl=http://img.medscape.com/fullsize/migrated/462/703/pharm462703.fig6.gif&imgrefurl=http://www.medscape.com/viewarticle/462703_5&usg=__z80IrPU5BiTFOiPF1Tl_LGkfCME=&h=438&w=500&sz=23&hl=nl&start=0&zoom=1&tbnid=msV9HhMcF-DiJM:&tbnh=128&tbnw=146&ei=xO-xTZqRDcuWOqqW1YkJ&prev=/search%3Fq%3DPatrick%2BKS,%2BStraughn%2BAB,%2BJarvi%2BEJ,%2BBreese%2BGR,%2BMeyer%2BMC.%2BThe%2Babsorption%2Bof%2Bsustained-release%2Bmethylphenidate%2Bformulation%2Bcompared%2Bto%2Ban%2Bimmediate-release%2Bformulation.%2BBiopharm%2BDrug%2BDispos%2B1989%253B10:165-71.%26um%3D1%26hl%3Dnl%26sa%3DN%26biw%3D1111%26bih%3D538%26tbm%3Disch&um=1&itbs=1&iact=hc&vpx=443&vpy=65&dur=827&hovh=210&hovw=240&tx=124&ty=122&page=1&ndsp=6&ved=1t:429,r:2,s:0.
As you can see, Concerta, because it is a mixture of instant and extended release, yields an initial peak in blood levels as Ritalin does, only less high. The it plateaus for a while; and then, blood levels continue to rise slowly until they begin to wear off after some eight hours. There we have it again: declining blood levels is what my brain doesn't like.
Interestingly, methylphenidate affects the amygdala - that part of the brain where emotions and memories are intertwined: http://ukpmc.ac.uk/abstract/MED/20208527/reload=0;jsessionid=0CE8457BBD94C9A2D3B10E2B43F5C790.jvm4. The euphoria I experience with peaking blood levels may have its counterpart in the dysphoric meltdown that begins when blood levels start waning.
Now, Concerta has a very innovative delivery system, based on research findings that show that climbing blood levels are most effective for improving performance. I could prevent the eight-hour u-turn by adding Ritalin before blood levels drop.
But my question for you is: what are your experiences with Ritalin IR and Concerta? Do you think there still is a place for Ritalin? Is Concerta tailor fit for your needs? Or do you rely on DIY Ritalin performance-management? Or combine both?
Thanks in advance for any answers and/or feedback.
Current meds: clomipramine 225mg, fluvoxamine (Luvox) 50mg, methylphenidate 30-90mg, flupentixol 1mg. PRN: oxazepam 5-20mg or other benzo's.
poster:Brainbeard
thread:983585
URL: http://www.dr-bob.org/babble/20110418/msgs/983585.html