Possible interactions include:

  • Antidepressants and other drugs and supplements that increase levels of serotonin. Don’t take SAMe with antidepressants. The combination could cause effects similar to a condition caused by high levels of the chemical serotonin to accumulate in your body (serotonin syndrome).
  • Antipsychotics. Be cautious when taking these drugs with S-Adenosylmethionine. The combination could increase the risk of serotonin syndrome.
  • Amphetamines. Be cautious when taking these drugs with S-Adenosylmethionine. The combination could increase the risk of serotonin syndrome.
  • Dextromethorphan. Taking SAMe with this cough suppressant could increase the risk of serotonin syndrome.
  • Levodopa. SAMe might reduce the effectiveness of levodopa (Inbrija), a medication used to treat Parkinson’s disease.
  • Narcotics. Taking SAMe with meperidine (Demerol) or tramadol (Ultram, ConZip) could increase the risk of serotonin syndrome.
  • St. John’s wort. Be cautious when taking this supplement with SAMe. The combination could cause serotonin syndrome.