Signs & Effects of Marijuana Use

Marijuana is the flowers, stems, and leaves of various subspecies of the Cannabis sativa plant.1 Contained within these plants is the psychoactive chemical delta-9-tetrahydrocannabinol, known as THC, which is primarily responsible for its mind-altering effects.2,3 This article will dive deeper into what the effects of marijuana are, health risks associated with marijuana use, and what signs of marijuana use can look like.

Short-Term Effects of Marijuana Use

When someone uses marijuana, THC activates cannabinoid receptors in the brain, causing a person to experience the desired effects of relaxation and euphoria.2,3 Smoking or vaporizing marijuana produces desired effects almost immediately and with relatively great intensity as the THC in the smoke or vapor passes through the lungs and  into the bloodstream.2,4 The effects then taper off quickly within a period of 1-3 hours.4 Eating or drinking the equivalent amount of THC delays the onset of these effects by 30-60 minutes with a more gradual rise and fall in intensity with a longer total duration (sometimes by several hours).5,6

Other short-term effects of marijuana can include the following:2,3

  • Distorted senses (seeing brighter colors, for example)
  • Changes in perception of time
  • Impaired memory
  • Difficulty thinking
  • Changes in mood
  • Impaired body movement and coordination

It is also possible for a person to experience psychosis or symptoms of psychosis (hallucinations, delusions, and loss of personal identity), however that risk is greater when taking high doses of marijuana.2

Additionally, not everyone who uses marijuana will experience the same effects over the same time period, as factors such as individual biology, how potent the marijuana is, how much is being consumed and the pattern of use can impact the effects that are felt, their duration, and intensity.6

Health Effects and Risks of Marijuana Use

Marijuana use puts a person at risk of experiencing several negative health effects.2 These effects and risks are more likely to occur with longer use and higher dose use, and some may result in long-term disability or carry long-term consequences. These health risks include:7

  • Lungs – Smoking marijuana chronically can negatively affect lung tissues, cause scarring, and even damage small blood vessels.
  • Brain – Marijuana is heavily linked to issues relating to attention, decision-making, coordination, memory, and reaction time. Individuals with developing brains, such as babies, children, and adolescents, are at greater risk for experiencing the damaging long-term effects of marijuana use and the exposure it can have on the brain.
  • Heart – One of the short-term effects of marijuana use can include increased heart rate, which can contribute to higher blood pressure over time. Marijuana can also increase one’s risk of experiencing a stroke or developing vascular diseases including heart disease when it is used chronically .
  • Mental health – While marijuana use has not been proven to directly cause mental health disorders, it has been associated with their effects or the worsening of their effects. Continual, long-term marijuana use can contribute to the effects associated with depression, social anxiety, and schizophrenia.
  • Driving – Marijuana can impact one’s ability to drive safely, as it can affect reaction time and coordination, distort perception, and affect one’s ability to make decisions.

Long-term and high-dose use of marijuana may also increase the likelihood of marijuana use disorder (or addiction) which is characterized by compulsive, uncontrollable use despite significant negative consequences.8

Signs of Marijuana Addiction

There are several signs that can indicate that someone may be experiencing marijuana use disorder, or marijuana addiction. The Diagnostic and Statistical Manual of Mental Disorders (DSM-5) outlines 11 criteria specific to substance use disorders like marijuana addiction. A person receives a diagnoses of marijuana use disorder after they are screened by a qualified mental health professional and they meet 2 of the 11 criteria in a 12-month period.9

Some of these criteria include, but are not limited to, the following:9

  • Using marijuana in large amounts or for longer than originally intended
  • Continuing to use marijuana despite having recurrent social or interpersonal problems related to marijuana use
  • Continuing to use marijuana despite knowing that it is causing and/or exacerbating physical or psychological issues
  • Being unable to fulfill obligations and responsibilities at work, home, or school due to marijuana use
  • Spending a great deal of time obtaining and using marijuana and recovering from marijuana effects

If you suspect that you or someone you love is experiencing marijuana use disorder, it can be helpful to review this information, but imperative to reach out to a professional for diagnostics and further steps.

Treatment for Marijuana Addiction

Like addictions to other drugs, marijuana addiction can be managed with similar treatment interventions. Studies show that treating marijuana addiction with evidence-based therapies and medications (in the event the patient has a co-morbid psychiatric disorder) can help decrease marijuana misuse, especially in those who have been misusing it heavily and for long periods of time.10

At our inpatient drug and alcohol rehab in Mississippi, we offer various levels of addiction treatment to help address the core issues related to one’s substance use so that you can adopt new ways to better manage stressors and other triggers that might otherwise result in unhealthy substance use. We encourage you to call us right now at to speak with one of our experienced rehab admissions navigators. They can answer all of your questions, including those regarding rehab insurance coverage and paying for addiction treatment.

Do not wait any longer to get the support that you or your loved one needs. Get started right now by filling out our secure online and have your insurance verified within minutes.

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