The purpose of this study is to understand the direct effects of cannabis on male reproductive functions. The investigators plan to conduct a double-blind, placebo-controlled clinical trial to examine both the chronic and acute effects of cannabis use on male reproductive functions. Specifically, the investigators will examine the dose-dependent effects of acute cannabis use on male reproductive parameters, including sperm counts, motility, morphology, and testosterone levels, as well as sperm epimutations.

Participants [cannabis users will be randomly assigned to 1) non-vaping, 2) placebo (vaping without cannabis), and 2 doses of cannabis, 3) 20 and 4) 40mg of THC in cannabis flower obtained from the NIDA drug supply], and 5) non-cannabis users (naïve control, no cannabis or placebo exposure).

Participants will provide surveys (cannabis use and sexual functioning and satisfaction etc.), peripheral blood, and semen.

The Volcano Vaporizer will be used to expose cannabis or placebo plants.

Inclusion Criteria:

• Regular cannabis users (21~64 years-old men) who have used cannabis at least once a week for at least once a year or who have never used cannabis.
• Willingness to abstain from using cannabis on the day of the testing session (minimum 5 hours abstinence).

Exclusion Criteria:

• Women
• Adult men, 65 or older, and men under the age of 21
• Serious psychiatric conditions (e.g. psychosis, bipolar I and panic disorder)
• Family history of psychosis
• Chronic medical conditions (e.g., heart disease, diabetes)
• History of adverse experiences with cannabis (e.g., anxiety and panic attacks)
• Use of other illicit drugs (not cannabis) in the past 2 months
• Heavy alcohol use (>4 drinks, >4 times/week)
• Smoking/nicotine use
• Infrequent cannabis use (less than once a week for only cannabis users)
• BMI over 34
• Current use of corticosteroids and blood thinners

Only biological men are eligible

This is our first small study to obtain preliminary results. We plan to propose to investigate the effects of acute and chronic cannabis exposure on male reproductive functions in humans, which include single or multiple cannabis vaping exposures and multiple semen collections in the same individual with a larger sample of participants. The data from the large study will be shared.