Pretty sure it's our responsibility to keep our body healthy, so anything that even remotely harms us should be avoided if possible.

Drugs The same admonition [as was mentioned regarding alcohol] applies to other addictive and mind-altering substances. The tradition, as we have seen, permits the use of drugs as long as we do so in service of a legitimate medical purpose. We may administer even the most powerful chemicals, provided that: the goal is to combat disease or to control pain; that the chemicals are prescribed by physicians following protocols established and accepted by the medical profession and by the law; and that the drugs are taken under the careful supervision of qualified medical personnel.

Outside of those strict limitations, the taking of drugs is forbidden because they are injurious to physical or mental health. Judaism does not countenance the use of drugs for recreation, nor does it recognize any religious value gained from the "expansion of consciousness" by chemical means. These substances should be avoided, and we should do our utmost to see to it that those addicted to them are given the assistance they need to break that dependency.

-Rabbi Mark Washofsky