You shouldn't use this drugs If you're already using an analogous opioid drugs and they are tolerant to it. Don't use this drugs When you've got employed a MAO inhibitor in past times 14 days, such as isocarboxazid, linezolid, phenelzine, rasagiline, selegiline, or tranylcypromine or have acquired a methylene blue injection.Really should not be pre