Long-term heavy use of marijuana may cause two important brain structures to shrink, Australian researchers said on Monday. Brain scans showed the hippocampus and amygdala were smaller in men who were heavy marijuana users compared to nonusers, the researchers said.

Ironically, just two days prior to the Drug Czar’s much ballyhooed press conference, Britain’s Advisory Panel on the Misuse of Drugs refuted the notion that pot use causes mental illness, stating, “The evidence for the existence of an association between frequency of cannabis use and the development of psychosis is, on the available evidence, weak.”

Health professionals -- both intentionally and unwittingly -- and dishonest patients are diverting powerful and potentially addictive pharmaceuticals from legitimate medical channels, authorities say.

Ever since California voters became the first in the nation to legalize medical marijuana in 1996, the state has faced unyielding opposition from the federal government, which insists it has the power to prohibit a drug it considers useless and dangerous. That could all change with the next presidential election.

For many modern critics, the concept of "medical marijuana" is a contradiction in terms. Medicine -- in its most powerful and privileged forms -- rests in the hands of men, while the most potent form of marijuana is found in the female flowering plant. Medicine engages in heroic battles against death. Marijuana claims only to enhance the quality of life.

Half of all Americans take prescription medications. Eighty one percent take some type of pill. 100,000 die every year from a prescription med that they either didn't need or that was not properly prescribed. What is going on here?

Celebrity magazines all too often feature stories about overdose deaths and rehab admissions, and the Office of National Drug Control Policy is running an advertising campaign about the dangers of prescription drug abuse. But when taken as prescribed, just how risky are drugs like OxyContin and Vicodin?

Using a brain imaging technology called functional magnetic resonance imaging (fMRI), scientists have discovered that cocaine-related images trigger the emotional centers of the brains of patients addicted to drugs -- even when the subjects are unaware they've seen anything.

Brain scans have revealed a possible biological basis for cocaine addiction which may explain why some get hooked, while others can use the drug socially. The scans show cocaine alters parts of the brain controlling behaviour and appropriate decision-making.

Marijuana smokers can develop gum disease even if they don't also smoke cigarettes, according to new research.