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Know Your Limit - Cannabis


Unlike alcohol, there is currently no definitive amount of cannabis that defines a standard dose. This means there is no quantifiable low to high-risk amounts on which to base recommendations. The National Institute on Drug Abuse has recently established 5 milligrams of delta-9-THC (the primary psychoactive component and what causes the effects that people most associate with getting “high”) as a standard unit of measurement for which researchers will base studies off. This offers some confidence that we will be able to provide similar guidance for cannabis as we do with alcohol in the near future.

Not all cannabis is created equal. Different strains of cannabis have THC concentrations that vary widely so when a person smokes cannabis (flower), one puff, drag, or hit is not equal to the next. The same is true of THC concentrates, which also vary widely and often start at much more potent levels. Edible products also come in different levels of THC and therefore each has different serving sizes. All of this complicates the ability to know and exact "dose" from one product to the next.

Because cannabis can be consumed in multiple ways, and the route of administration can significantly affect the way in which the body metabolizes and synthesizes the compounds in the plant, it can cause experiences to vary widely from the type of cannabis and from person to person. With that in mind, here we explore all the factors to be mindful of when choosing to consume cannabis and what to look out for as signs that a person has consumed too much.


When smoked, vaped, or dabbed THC enters the bloodstream almost instantly and the effects are felt within minutes. When people make claims that cannabis is not harmful they are typically referring to when people are smoking flower as it can be hard to ingest significant enough levels of THC this way to pose a serious risk from the drug alone. However, higher THC concentrations found in strains produced today can be harmful when consumed in large quantities. Subsequently, THC concentrates, sometimes containing as much as 80% THC or more, pose an increased risk when smoked/vaped/dabbed because it only takes a small amount of a concentrate to equal or surpass the amount of THC that would be contained in a full joint or bowl of flower.


When THC is consumed by eating or drinking an infused product (edibles) the body processes the THC more slowly and differently. When THC is processed through the GI tract and liver, the body converts delta-9-THC into the more potent 11-Hydroxy-THC. This can result in far more intense highs and adverse health effects. 

How Long Does The High Last?

It is extremely important to understand that the effects of THC can last far longer than you may expect or want them to. Below are some general guidelines from Drugs and Me, but know that this can vary by person and by how much THC you have ingested.

Understanding The Effects of Short Term Cannabis Use

This is a general guide and should not be considered as definitive in how you or another person will react and present after consuming cannabis. Everyone is different and numerous factors (biological makeup, overall health, type of cannabis, route of administration, environment, etc.) can impact how a person reacts to cannabis and its effects. To reduce the likelihood of a negative experience, never consume more cannabis than is associated with the effects that correspond with a low level of risk.

Amount of THC Consumed/Level of Risk Feelings Associated With Amount of Use



Distorted Sense of Time and Space
Alteration of Sight and Smell
Mild Pain Relief
Increased Heart Rate

Impairment of Short Term Memory
Slurred Speach
Impaired Motor Function
Signs of a Cannabis Overdose

It is possible to ingest too much cannabis, which can result in unpleasant and serious conditions that can last for multiple hours. Never leave a person in this condition alone. Always seek medical attention if they are unresponsive, in distress or symptoms worsen. 

Internal Signs & Feelings External Signs & Behavior
  • Paranoia
  • Anxiety
  • Hallucinations
  • Altered sense of perception or delusions
  • Decreased blood pressure/dizziness
  • Fast heartbeat
  • Pale skin
  • Incoherent
  • Extreme Confusion/Memory Problems
  • Unresponsiveness
  • Vomiting and/or nausea
  • Shaking that’s hard to control
How To Reduce Harm

Now that you know more about the various forms THC can come in and how the route of administration influences the body’s response to the drug, here are some tips on how to reduce negative consequences when using cannabis:

Know the Laws

Regardless of cannabis being legalized in the state of Illinois for adults 21+, Northwestern must adhere to federal guidelines. Therefore, it is still illegal to possess and/or use cannabis on University grounds or at University-sponsored events. Learn more on the Cannabis Policy FAQ page.