I just stumbled over this, but it seems that it cut the DK by half! And, since it is an NMDA antagonist (as is dextromethorphine) it might have even more surprises. Anyone ever try it for DK? (Note that this would be in the hidden treasure class since it can't be patented. So the research simply hasn't been done.)

1: Exp Neurol. 2003 Aug;182(2):490-6.

Antidyskinetic effect of magnesium sulfate in MPTP-lesioned monkeys.

Chassain C, Eschalier A, Durif F.

Unité INSERM EMI 9904, Faculté de Médecine et Pharmacie, 28, place Henri-Dunant,
63001, Clermont-Ferrand, France. kchassin@clermont.inra.fr

The antiparkinsonian action of an NMDA receptor antagonist, magnesium sulfate
(50, 100, and 200 mg/kg), alone and in association with levodopa was explored in
1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-lesioned parkinsonian and
control rhesus monkeys. At the three doses tested, magnesium sulfate decreased
levodopa-induced dyskinesia [cumulative dyskinetic scores after levodopa: 129 +/-
13; after levodopa and magnesium sulfate: 65 +/- 14 (50 mg/kg), P < 0.001; 64 +/-
10 (100 mg/kg), P < 0.001; 66 +/- 21 (200 mg/kg), P < 0.001, compared to levodopa
administration alone]. These results show that magnesium sulfate importantly
reduces levodopa-induced dyskinesia.


PMID: 12895461 [PubMed - indexed for MEDLINE]