This is the 2007 version. Click here for the 2017 chapter 03 table of contents.


Heroin and morphine

What does heroin resemble? Is it immediately pleasurable?

Heroin and morphine are opiates, substances that resemble the body's natural pain-fighting substances: endorphins. Endorphins are secreted into the bloodstream naturally during times of stress. They reduce physical and psychological pain and may produce a diffuse feeling that all is well. However, the first time a person takes heroin, it may not even be pleasurable. Beecher (1959) gave non-addicted subjects injections of heroin or a harmless placebo. The subjects preferred the placebo.

Sandoz (1922) made these comments about morphine, a derivative of heroin:

What is the "most striking thing" about morphine effects, in ordinary doses? What happens after the "honeymoon" phase?

The widely spread belief that morphine brings about an uncanny mental condition, accompanied by fantastic ideas, dreams, and whatnot, is wrong... The most striking thing about morphine, taken in ordinary doses by one who is not an addict, is that it dulls general sensibility, allays or suppresses pain or discomfort, physical or mental, whatever its origin, and that disagreeable sensations of any kind, including unpleasurable states of mind are done away with. In fact, the suppression of pain is the only outstanding effect of morphine... The more normal a person feels, the less marked...the effects will be. (p.12)

Although Sandoz did not find the effects of morphine irresistible, some people (perhaps those in chronic pain, physical or psychological) immediately want to repeat the experience. That is why heroin has one of the highest capture ratios of any drug. As with other drugs, a user may experience, at first, a "honeymoon" phase during which the drug is highly enjoyable. The honeymoon ends when the body adjusts to the drug. Soon the addict requires larger doses to get a smaller high. In the end, a hard-core user feels little euphoria at all from taking the drug but—as with cocaine and methamphetamine—must have it to feel normal. Sandoz gives this description:

How did the chronic user of morphine feel?

The same dose will become less and less effective, or must be increased in order to obtain the same effect. More than this, the original feeling of unusual well-being can no longer be obtained; under the influence of morphine the chronic user will simply feel "normal." (Sandoz, 1922, p.13)

Why is dependence greatest when enjoyment fades?

Why does the addict require progressively higher doses? The body adapts to constant presence of the drug and learns to combat it with natural opiate antagonists —chemicals that reduce the effects of opiates. If opiates are constantly added to the body, the body starts producing antagonists in large amounts, neutralizing the effect of the drug. However, this also means the addict will feel great pain if he or she stops taking the drug. The body's own pain-relief system, involving relatively low levels of endorphins, has little effect in the presence of high concentrations of opiate antagonists. This explains why dependence is greatest just when enjoyment starts to fade: both are the result of high levels of antagonists. At that point, if a person tries to quit, the result is great pain.

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Copyright © 2007-2011 Russ Dewey