Assessment: Symptomatic treatment for muscle cramps (an evidence-based review)
AlexanderMauskop, New York Headache Center
Published June 17, 2010
Katzberg et al. analyzed two negative papers regarding the use of magnesium citrate for the treatment of muscle cramps. [1]
They omitted a positive double-blind trial where proprietary "primarily magnesium lactate, magnesium citrate" product was used. [2] However, "symptomatic" in the paper by Katzenberg et al. implies that no underlying cause has been detected, while muscle cramps are a typical symptom of magnesium deficiency [3] and it would be more appropriate to consider hypomagnesimia as a specific, correctable cause.
Due to the benign nature and low cost of magnesium, empiric therapy with magnesium in all patients may be worthwhile. However, oral magnesium is often poorly absorbed and lack of a response to treatment does not rule out the presence of magnesium deficiency. Serum levels are not useful because only 1% of magnesium in the body is extracellular and there is poor correlation between serum and the more accurate RBC or ionized magnesium levels.
Since ionized levels are not commercially available and RBC magnesium levels are fairly expensive (about $80 US), an empirical trial with magnesium oxide, magnesium citrate, or a chelated form of magnesium is warranted. However, in severe cases, measuring RBC magnesium levels and administration of IV magnesium sulfate can be considered.
References
1. Katzberg HD, Khan AH, So YT. Assessment: Symptomatic treatment for muscle cramps (an evidence-based review): Report of the Therapeutics and Technology Assessment Subcommittee of the American Academy of Neurology. Neurology 2010;74:691-696.
2. Dahle L, Berg G, Hammar M, Hurtig M, Larsson L. The effect of oral magnesium substitution on pregnancy-induced leg cramps. American Journal of Obstetrics and Gynecology 1995:173;175-180.
3. Coghlan HC, Natello G. Erythrocyte magnesium in symptomatic patients with primary mitral valve prolapse: relationship to symptoms, mitral leaflet thickness, joint hypermobility and autonomic regulation. Magnes Trace Elem. 1991-1992;10:205-214.
Disclosure: Dr. Mauskop owns patents for Migralex and is part owner of Migralex, Inc.
Katzberg et al. analyzed two negative papers regarding the use of magnesium citrate for the treatment of muscle cramps. [1]
They omitted a positive double-blind trial where proprietary "primarily magnesium lactate, magnesium citrate" product was used. [2] However, "symptomatic" in the paper by Katzenberg et al. implies that no underlying cause has been detected, while muscle cramps are a typical symptom of magnesium deficiency [3] and it would be more appropriate to consider hypomagnesimia as a specific, correctable cause.
Due to the benign nature and low cost of magnesium, empiric therapy with magnesium in all patients may be worthwhile. However, oral magnesium is often poorly absorbed and lack of a response to treatment does not rule out the presence of magnesium deficiency. Serum levels are not useful because only 1% of magnesium in the body is extracellular and there is poor correlation between serum and the more accurate RBC or ionized magnesium levels.
Since ionized levels are not commercially available and RBC magnesium levels are fairly expensive (about $80 US), an empirical trial with magnesium oxide, magnesium citrate, or a chelated form of magnesium is warranted. However, in severe cases, measuring RBC magnesium levels and administration of IV magnesium sulfate can be considered.
References
1. Katzberg HD, Khan AH, So YT. Assessment: Symptomatic treatment for muscle cramps (an evidence-based review): Report of the Therapeutics and Technology Assessment Subcommittee of the American Academy of Neurology. Neurology 2010;74:691-696.
2. Dahle L, Berg G, Hammar M, Hurtig M, Larsson L. The effect of oral magnesium substitution on pregnancy-induced leg cramps. American Journal of Obstetrics and Gynecology 1995:173;175-180.
3. Coghlan HC, Natello G. Erythrocyte magnesium in symptomatic patients with primary mitral valve prolapse: relationship to symptoms, mitral leaflet thickness, joint hypermobility and autonomic regulation. Magnes Trace Elem. 1991-1992;10:205-214.
Disclosure: Dr. Mauskop owns patents for Migralex and is part owner of Migralex, Inc.