Inclusion Criteria:

   - Taking vismodegib daily

   - Subject answers item #1 of muscle spasms questionnaire as moderate or severe intensity
   at time of screening

   - At least one muscle spasm per day at time of screening

   - Muscle spasms onset after starting vismodegib

   - Willing and able to understand and sign consent form

Exclusion Criteria:

   - Presence of muscle spasms or active neurologic disease prior to start of vismodegib

   - Use of thyroid medication at the time of screening

   - Use of Coumadin or acenocoumarol at time of screening

   - Change in regimen of muscle relaxant medications within four weeks of enrollment

   - If on stable muscle relaxant medication regimen for 4 weeks prior to enrolling, not
   willing to maintain muscle relaxant regimen without change during course of the study

   - Presence of significant renal disease or hemodialysis which would result in dramatic
   reductions of systemic levocarnitine levels

   - History of seizures

   - Known deficiency in carnitine (genetic, etc.)

   - Any uncontrolled medical condition which may place the patient at increased risk
   during study participation (at the discretion of the clinical investigator)

   - Unable or unwilling to comply with study procedures

   - Pregnant or lactating

   - All female patients of childbearing potential including those who are within 1 year of
   last menstrual period will be required to take a pregnancy test during screening,
   enrollment and at week 0, 4, 8 and 12

   - If female of reproductive age, or male partner of female of reproductive age,
   unwilling to use two medically reliable forms of birth control while on vismodegib

   - Unwilling to refrain from donation of bodily fluid (blood, platelets, etc.) within 7
   months of last vismodegib dose