Effect of systemic monosodium glutamate (MSG) on headache and pericranial muscle sensitivity

Department of Clinical Oral Physiology, School of Dentistry, University of Aarhus, Aarhus, Denmark.
Cephalalgia (Impact Factor: 4.89). 04/2009; 30(1):68-76. DOI: 10.1111/j.1468-2982.2009.01881.x
Source: PubMed


We conducted a double-blinded, placebo-controlled, crossover study to investigate the occurrence of adverse effects such as headache as well as pain and mechanical sensitivity in pericranial muscles after oral administration of monosodium glutamate (MSG). In three sessions, 14 healthy men drank sugar-free soda that contained either MSG (75 or 150 mg/kg) or NaCl (24 mg/kg, placebo). Plasma glutamate level, pain, pressure pain thresholds and tolerance levels, blood pressure (BP), heart rate and reported adverse effects were assessed for 2 h. No muscle pain or robust changes in mechanical sensitivity were detected, but there was a significant increase in reports of headache and subjectively reported pericranial muscle tenderness after MSG. Systolic BP was elevated in the high MSG session compared with low MSG and placebo. These findings add new information to the concept of MSG headache and craniofacial pain sensitivity.

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    • "Although the MSG was dissolved in sugar free lemon soda, which we have previously found masks the taste of MSG [13], the vast majority of subjects correctly identified the substance administered to them when asked at the end of each 5 days session. Considering the significant increase in adverse effects, which occurred during MSG ingestion, this result is understandable. "
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