Relative Addictiveness of Various Substances

In Health, Nov/Dec 1990

"To rank today's commonly used drugs by their addictiveness, we asked experts to consider two questions: How easy is it to get hooked on these substances and how hard is it to stop using them? Although a person's vulnerability to drug also depends on individual traits -- physiology, psychology, and social and economic pressures -- these rankings reflect only the addictive potential inherent in the drug. The numbers below are relative rankings, based on the experts' scores for each substance:

100 Nicotine

99 Ice, Glass (Methamphetamine smoked)

98 Crack

93 Crystal Meth (Methamphetamine injected)

85 Valium (Diazepam)

83 Quaalude (Methaqualone)

82 Seconal (Secobarbital)

81 Alcohol

80 Heroin

78 Crank (Amphetamine taken nasally)

72 Cocaine

68 Caffeine

57 PCP (Phencyclidine)

21 Marijuana

20 Ecstasy (MDMA)

18 Psilocybin Mushrooms

18 LSD

18 Mescaline

Research by John Hastings

Relative rankings are definite, numbers given are (+/-)1%



Is Nicotine Addictive?

Philip J. Hilts, New York Times, August 2, 1994

Experts Rate Problem Substances

Dr. Jack E. Henningfield of the National Institute on Drug Abuse and Dr. Neal L. Benowitz of the University of California at San Francisco ranked six substances based on five problem areas.

Withdrawal: Presence and severity of characteristic withdrawal symptoms.

Reinforcement: A measure of the substance's ability, in human and animal tests, to get users to take it again and again, and in preference to other substances.

Tolerance: How much of the substance is needed to satisfy increasing cravings for it, and the level of stable need that is eventually reached.

Dependence: How difficult it is for the user to quit, the relapse rate, the percentage of people who eventually become dependent, the rating users give their own need for the substance and the degree to which the substance will be used in the face of evidence that it causes harm.

Intoxication: Though not usually counted as a measure of addiction in itself, the level of intoxication is associated with addiction and increases the personal and social damage a substance may do.

HENNINGFIELD RATINGS 1 = Most serious 6 = Least serious


Substance Withdrawal Reinforcement Tolerance Dependence Intoxication


Nicotine 3 4 2 1 5

Heroin 2 2 1 2 2

Cocaine 4 1 4 3 3

Alcohol 1 3 3 4 1

Caffeine 5 6 5 5 6

Marijuana 6 5 6 6 4


BENOWITZ RATINGS 1 = Most serious 6 = Least serious


Substance Withdrawal Reinforcement Tolerance Dependence Intoxication


Nicotine 3* equal 4 4 1 6

Heroin 2 2 2 2 2

Cocaine 3* equal 1 1 3 3

Alcohol 1 3 4 4 1

Caffeine 4 5 3 5 5

Marijuana 5 6 5 6 4

SEE this

Cannabis and hallucinogens - not toxic

caffeine 10,000mg, = 100 cups of coffee

barbiturates 2,000mg

amphetamine and cocaine 1,000mg

heroin 120-350mg

nicotine 60mg


Are all drugs addictive?

From DrugScope has been created through the merger of the UK's foremost drug information and policy organisations: the Institute for the Study of Drug Dependence (ISDD) and the Standing Conference on Drug Abuse (SCODA) - two charities with a total of sixty years in the national and international drugs field.

"Continual use of drugs like cannabis, ecstasy and LSD does not result in physical dependency, even though people may become psychologically dependent. With other drugs and particularly stimulant drugs such as cocaine, crack, amphetamine and the nicotine in cigarettes there is debate over the extent that physical dependence can occur."

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