http://www.cc.nih.gov/ccc/patient_education/drug_nutrient/lithium1.pdf
NIH Clinical Center, National Institutes of Health
While you are taking lithium, your doctor will monitor the lithium level in your blood. High lithium levels can cause shakiness, muscle weakness, slurred speech, nausea or vomiting, and drowsiness. This brochure provides diet guidelines to help you keep your lithium blood level stable.