This Initiation, Take it Very Seriously - Prabhupada 0042.

Intoxication

Intoxication refers to the taking into the body of various chemicals that are not necessary for bodily maintenance and have stimulating or depressive effects on the mind and body. Under this heading the Vedic scriptures include everything from tea, coffee and tobacco, with their caffeine and nicotine, to liquor and other more powerful drugs. Countless people in this age depend on some such intoxicants for stimulation or relief from anxiety, but any objective observer will conclude that such enjoyment or relief is only transitory and therefore has no real substance.

Instead, there are many detrimental results coming from such intoxicating habits. They cause dependency on material, worldly supports that are never certainly available, and this dependency can increase with the strength of the intoxicant, up to the point of addiction. These habits generally cause loss of bodily or mental health, resulting eventually in disease, premature aging, and inability to fix the mind intelligently and steadily on any subject or problem. In this way, such habits impede spiritual advancement by binding a person with material attachments and at the same time agitating the mind so that it cannot be fixed in meditation on the self and God. Beyond this, with the use of stronger and stronger intoxicants, cleanliness is gradually destroyed—witness the usual living conditions of addicts, alcoholics and drug-dependent hippies—and the mind is led into degradation and a miserable future. Of course, the stronger the intoxicant, the more pronounced the effects, but we can easily observe in these days how the use of milder intoxicants gradually leads toward dependence on stronger ones.

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