- Medication exclusion criteria - current use or recent discontinuation (within last 28 days) of any medication including the following: anti-coagulants and blood-thinners (e.g., Warfarin), psychotropic medications including antipsychotics, mood-stabilizers (e.g., lithium, valproic acid, carbamazepine/tegretol); anti-depressants (tricyclics, SSRI's, MAOI's, nonselective MAOIs, Wellbutrin, St. John's Wort); anti-anxiety/anti-panic agents; anti-obsessive agents; prescription stimulants (e.g., Provigil, Ritalin); diet pills/anorectics; daily medication for chronic pain (e.g., opiates) or muscle spasms; daily use of over the counter stimulants in pill form (e.g., ephedrine); daily medication for asthma, Parkinson's disease medications (e.g., levodopa, methyldopa, apomorphine), smoking cessation medications (Wellbutrin/Zyban, Chantix/varenicline)