NMDA receptor antagonists amantadine

Kornhuber J, Quack G, Danysz W, Jellinger K, Danieiczyk W, Gsell W, Riederer P. (1995). Therapeutic brain concentration of the NMDA receptor antagonist amantadine. Neuropharmacology. 34(7) 713-21. 

Pud, D., Eisenberg, E., Spitzer, A., Adler, R., Fried, G., Yarnitsky, D. The NMDA receptor antagonist amantadine reduces surgical neuropathic pain in cancer patients a double blind, randomized, placebo controlled trial, Pain 1998, 75, 349-354. 

Eisenberg, E., Pud, D., 1998. Can patients with chronic neuropathic pain be cured by acute administration of the NMDA receptor antagonist amantadine . Pain 74, 337-339. 

Amantadine (Symmetrel ) NMDA-receptor antagonist that blocks glutamate transmission, promotes DA release, and blocks Ach Start with 1 00 mg daily at breakfast after 1 week, add 1 00 mg daily in the early afternoon decrease dose as creatinine clearance decreases less than... 

Memantine (Namenda) [Anti Alzheimer Agent/NMDA Receptor Antagonist] Uses Mod/ evere Alzheimer Dz Action N-methyl-D-aspartate recqjtor antagonist Dose Target 20 mg/d, start 5 mg/d, t 5 mg/d to 20 mg/d, wait >1 wk before t dose use doses if >5mg/d Caution [B, /-] Hqjatic/mild-mod renal impair Disp Tabs, sol SE Dizziness Interactions t Effects W amantadine, carbonic anhydrase inhibitors, dextromethorphan, ketamine, Na bicarbonate t effects W/ any drug, herb, food that alkalinizes urine EMS Use NaHCOs w/ caution OD May cause restlessness, hallucinations, drowsiness, and fainting symptomatic and supportive... 

In humans, the antidepressant activity of NMDA receptor antagonists has not been evaluated extensively (Skohiick 1999). In animal models of depression, NMDA receptor antagonists have been reported to exert positive effects in most studies (Trullas 1997). This concerns mainly the forced swim test (Maj 1992 Moryl et al. 1993 PrzegaUnski et al. 1997) and stress-induced anhe-donia (Papp and Moryl 1994). Amantadine but not memantine was effective against reserpine-induced hypothermia (Moryl et al. 1993). In the forced swim test, both amino-adamantanes produced specific antidepressive-like activity (Moryl et al. 1993). 

Memantine is not a major substrate for hepatic cytochrome P450 isoenzymes and has not been shown to significantly inhibit or induce these enzymes. However, memantine is partially excreted by renal tubular secretion. Thus, concomitant use of other medications that use the same renal system (i.e., triampterene, hydrochlorothiazide, digoxin, cimetidine, ranitidine, metformin, and quinidine) may affect plasma levels of both drugs (Namenda 2005). Memantine should not be used in combination with other NMDA receptor antagonists, such as amantadine or dextromethorphan, because these combinations have not been formally studied. The clearance of memantine can be reduced when the urine is alkalinized, such as with the concomitant use of sodium bicarbonate or carbonic anhy-... 

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