Linda -

In communications with a number of pain patients, who have had ketamine, both online and over the phone, I have been told that the only risk for pain actually increasing as a result of a ketamine infusion is the dose is to high, and then that can be corrected the next time around by a low ever dose, or so these patients have been advised by their physicians. Some discussion of this appears in a related thread on this page, follow-up ketamine question: can it ever make the pain worse? http://neurotalk.psychcentral.com/thread140113.html

(As I've mentioned elsewhere, although I was supposed to go to Germany for a ketamine coma in 2004, that died when the German physicians discovered that I had a history of open-angled glaucoma, where ketamine is known to raise eye pressures. That bar will hopefully be lifted as soon as USC's program is up and running - the 10 day outpatient infusions have been shown to significantly reduce pain six months out, even for patients with chronic CRPS - where an ophthalmology prof. at USC has agreed to oversee the monitoring of my eye pressures during the procedures, reversing any pressure spike with an IV dose of Diamox. Now it's just a matter of the allergists clearing me for the use of Diamox, a sulfa-derivative, where I had some fairly profound allergic reactions to sulfa drugs before getting RSD/CRPS, at which point my observable allergies vanished altogether, having possibly undergone a "T1/T2 immune shift" in the acute stage of the illness.)

The dose that is currently being used in the 10 day outpatient infusion program is 200 mg./4 hour infusion. This is the dose suggested in Outpatient Intravenous ketamine for the treatment of complex regional pain syndrome: a double-blind placebo controlled study, Schwartzman RJ, Alexander GM, Grothusen JR, Paylor T, Reichenberger E, Perreault M, Pain 2009 Dec 15;147(1-3):107-15, Epub 2009 Sep 23 FULL ONLINE TEXT @ http://www.rsds.org/2/library/articl...n_Pain2009.pdf, even though the study itself limited the 4 hour dose to 100 mg.

In contrast, and for your information, the companion thread referred to above indicates that in the starting infusion given by the poster’s physician "is about 1g over the four hours." (Page 2, post 15.) But even in the “high-dose” anesthetic treatment programs that was run over a number of years in Germany, “Treatment was maintained by infusions of ketamine over 5 days, starting at 3 mg/kg/h, followed by gradual daily titration up to a final dose of 7 mg/kg/h.” Efficacy of Ketamine in Anesthetic Dosage for the Treatment of Refractory Complex Regional Pain Syndrome: An Open-Label Phase II Study, Kiefer RT, Rohr P, Ploppa A, et al, Pain Med. 2008 Nov; 9(8):1173-201, FULL ONLINE TEXT @ http://www.rsds.org/2/library/articl...a_Dietrich.pdf Now, 1 pound = 0.45359237 kilograms, that means that a 140 lb. woman weighs approx. 63.5 kg. As a result, at the high end of the anesthetic ketamine program, where patients would be receiving 7 mg/kg/h, a 140 lb. patient would be getting 444.5 mg of ketamine/hour or 1.778 grams over a 4 hour period, which indeed is what the poster reported that she was getting herself, albeit not over a 5 – day period!

In light of the issues and concerns reported in follow-up ketamine question: can it ever make the pain worse?, I would be hesitant (and then some) to start off with an infusion rate of 1 gr./4 hours.


Mike