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Q&A: Cannabis

Cannabis 101: A Q&A with UC San Diego Health’s cannabis experts

It seems like everywhere you turn cannabis or cannabis derivatives can be found. From ingredients in coffee and smoothies to being marketed as medicine, a cannabis craze seems to be sweeping the country. Since 2000, UC San Diego School of Medicine’s Center for Medicinal Cannabis Research and its affiliated researchers have been studying marijuana and its derivatives, their effects on mind and body and their therapeutic potential.

We asked experts to cut through the hyperbole and haze to answer some burning questions.

What is the difference between CBD and THC?

How long does each stay in your system?

Would CBD be shown as a positive result in a THC drug test?

Has cannabis been shown to have an effect on pain?

Are there any long term health effects from cannabis use?

Answered by Grant

Looking at adults and cannabis, which has traditionally had low levels of THC, it appears that the health effects are fairly minimal. Some other popular questions we are asked include:

  • Does smoking cannabis cause lung cancer? The short answer is no, unless cannabis is used in combination with tobacco, and the culprit for cancer would be tobacco.
  • Does cannabis cause birth defects? There's no evidence to support this in humans.
  • Does cannabis cause your immune system to somehow malfunction? Again, there is no data to support this.
  • Does cannabis cause brain damage? The answer to this is very unlikely.

Q&A: Cannabis and driving study

Interview with Igor Grant, MD, Distinguished Professor and Chair of the Department of Psychiatry and director of the Center for Medicinal Cannabis Research and Thomas Marcotte, PhD, professor of psychiatry.

How does cannabis impact the body and how is it measured?

What type of cannabis is being used in this study?

Why did you decide to conduct this study?

How is this study designed?

Who is participating in this study?

What is the most innovative aspect of this study?

How are you collaborating with law enforcement on this study?

What kind of future research would be beneficial to understanding cannabis?