Hi, Brief answer: Always take medication as prescribed and abstain from using illicit drugs. Detailed answer: Antidepressant medications, including Lexapro and Effexor act on various chemicals and signals in the brain. These medications help to increase the amount of the chemical serotonin in the brain. Abruptly stopping these medications can cause serious side effects, in particular antidepressant discontinuation syndrome. Antidepressant discontinuation syndrome presents with difficulty sleeping, flu-like symptoms (fatigue, muscle aches, headache, feeling ill), electric shock-like sensations, and anxiety. Patients must be slowly weaned off these medications. Use of illicit drugs like Ecstacy is problematic, especially considering that you are already taking medications that influence your brain and central nervous system. Ecstacy has stimulant effects and acts by increasing the same chemicals in the brain as Lexapro and Effexor. If your serotonin levels increase too much it can cause Serotonin Syndrome, a very serious an potentially fatal complication involving very high blood pressure, fever, muscle rigidity, and seizures. I always advise patients to take their medications as prescribed. It is never advisable to abruptly discontinue a medication without speaking to a doctor before doing so. I strongly suggest that your inform your doctor that you have stopped taking your Lexapro and also of your use of illicit drugs. Take care. Hope I have answered your question. Let me know if I can assist you further. Regards, Dr. Aaron Shapiro, General & Family Physician