Medically Reviewed by: Dr. Dipak Ladda, M.D.
Expertise: Consultant Pathologist
Last Updated: August 3, 2026
Medical Analysis
Comprehensive Medical Analysis of Marijuana, Cannabis Pharmacology, and Urine Testing Protocols
Introduction to Cannabis and Molecular Overview
Cannabis, also known as marijuana or weed among other names, is a psychoactive drug from the cannabis plant [1, 5]. In various geographical regions this drug has been used for both recreational and entheogenic purposes and in various traditional medicines for many centuries [1, 5]. It is available in Dried leaves, flowers, stems, and seeds from the plant Cannabis sativa or Cannabis indica [5, 6]. The main psychoactive chemical in marijuana, responsible for most of the intoxicating effects that people seek, is delta-9-tetrahydrocannabinol (THC) [2, 3]. The chemical is found in resin produced by the leaves and buds primarily of the female cannabis plant [6, 7].
Detailed Classification of Cannabis Compounds
| Category | Description |
| Marijuana | Dried leaves and flowering heads [5, 6] |
| Hashish | Resin from upper leaves and flower buds [5, 6] |
| Non-cannabinoids | Isolated pure compounds [6, 7] |
| Cannabinoids: Psychoactive | Delta-9-THC, Delta-8-THC [2, 3] |
| Cannabinoids: Active but not psychoactive | Cannabidiol [2, 3] |
| Cannabinoids: Inactive | More than 60 compounds [6, 7] |
Metabolic Pathways and Biotransformation of THC
The metabolism of marijuana involves sequential breakdown steps starting from Delta-9-THC, which converts into 11-OH-THC, subsequently transforming into THC-COOH, and finally conjugating into Glucuronide [2, 3].
Physiological Functions and Organ System Effects
Cannabis exerts wide-ranging systemic effects across multiple organ systems through cannabinoid receptors [2, 4].
| Organ/System | Effects |
| Brain (CNS) | Euphoria, relaxation, altered perception, impaired memory, anxiety, psychosis (high dose) [2, 4] |
| Cardiovascular | Tachycardia, increased blood pressure (short-term), orthostatic hypotension, arrhythmias [2, 4] |
| Respiratory | Bronchodilation (acute), chronic bronchitis, cough, airway inflammation [1, 5] |
| Gastrointestinal | Increased appetite (“munchies”), nausea relief, cannabinoid hyperemesis (chronic) [1, 5] |
| Reproductive | Decreased sperm count, decreased testosterone, menstrual irregularities, fetal growth restriction [1, 5] |
| Immune System | Immunosuppression, altered cytokine response [1, 5] |
| Endocrine / Metabolic | Cortisol, insulin resistance (chronic use) [1, 5] |
| Eyes | Conjunctival congestion, decreased intraocular pressure (glaucoma) [2, 4] |
| Psychiatric | Dependence, mood swings, cognitive impairment, amotivation [1, 4] |
| Motor / Coordination | Slowed reaction time, impaired driving ability [2, 4] |
Clinical Indications for Drug Testing
Safeguarding individual health [20]
Public safety compliance [20]
Enabling informed decision-making in medical, legal, and occupational settings [20]
Rehabilitation and recovery [20]
Competitive Sports [20]
Laboratory Testing Methods, Sample Collection, and Reference Intervals
Drug testing utilizes various biological samples, with urine standing out as the most common drug testing method [8, 9]. Other sample types include blood, saliva, hair, and nails [8, 17, 18]. Laboratory detection methods include high-performance liquid chromatography (HPLC), gas chromatography-mass spectrometry (GC-MS), and immunoassay [8, 15, 16].
| Sample Collection Parameter | Protocol Details |
| Volume and Container | Collect 60 to 100 milliliters of random urine in sterile container [20]. |
| Storage/Transport Temperature | Room temperature [20]. |
| Stability Windows | Ambient: 1 week; Refrigerated: 1 month; Frozen: 1 month [20]. |
Reference Ranges and Cutoff Thresholds
| Analyte | Reference Interval in Urine | Notes |
| 11-Nor-9-carboxy-THC | 15 nanograms per milliliter [20] | This test does not distinguish between the delta-8 and delta-9 forms of THC or their metabolites [10]. |
Detection Windows and Clinical Significance
Urine testing is the most common trusted source drug testing method, though detection windows may vary based on usage frequency [8, 11]. Increased drug intake leads to elevated detection times [3, 11].
| Drug Use Frequency Profile | Detection Time in Urine After Last Use |
| Single-use | Up to 3 days [11] |
| Moderate use (2 to 4 times per week) | Up to 5 to 7 days [11] |
| Heavy use (daily) | Up to 10 to 30 days [11] |
| Chronic heavy use | Up to 60 to 90 days [11] |
For Non-Medicos
What Is Cannabis and How Does It Affect the Body?
Cannabis is a plant-based substance containing chemical compounds that alter mood, perception, and body functions [1, 5]. Its primary mind-altering ingredient is THC, which triggers feelings of euphoria, relaxation, and changed sensory perceptions, alongside potential side effects like increased heart rate, altered coordination, and dry eyes [2, 3, 4].
Testing for Marijuana and Understanding Urine Sample Results
Urine testing is the most widespread and trusted method used by employers, medical professionals, and athletic programs to check for recent drug use [8, 9, 20]. By analyzing a small urine sample in a lab using advanced techniques, specialists can detect non-active breakdown products of THC, showing whether an individual has consumed marijuana recently or over past weeks, depending on their usage habits [3, 8, 11].
References:
World Health Organization. The health and social effects of nonmedical cannabis use. World Health Organization; 2016.
Grotenhermen F. Pharmacokinetics and pharmacodynamics of cannabinoids. Clin Pharmacokinet. 2003;42(4):327-360.
Huestis MA. Human cannabinoid pharmacokinetics. Chem Biodivers. 2007;4(8):1770-1804.
Ashton CH. Pharmacology and effects of cannabis: a brief review. Br J Psychiatry. 2001;178(2):101-106.
National Academies of Sciences, Engineering, and Medicine. The Health Effects of Cannabis and Cannabinoids: The Current State of Evidence and Recommendations for Research. Washington, DC: The National Academies Press; 2017.
ElSohly MA. Chemical constituents of Cannabis sativa L. In: Pertwee RG, ed. Handbook of Cannabis. Oxford University Press; 2014:27-35.
Turner CE, ElSohly MA, Boeren EG. Constituents of Cannabis sativa L. XVI. A possible analytical evaluation of the geographical origin. J Nat Prod. 1980;43(2):299-306.
Lee D, Huestis MA. Current trends in forensic drug testing: cannabinoids in biological fluids and tissues. Forensic Sci Rev. 2006;18(2):77-102.
Moeller KE, Lee KC, Kissack JC. Urine drug screening: practical guide for clinicians. Mayo Clin Proc. 2008;83(1):66-76.
Pesce AJ, West C, Johnson RD, et al. Interpretation of urine assays for drug abuse. Clin Chem. 2012;58(3):512-520.
Verstraete AG. Detection times of drugs of abuse in blood, urine, and oral fluid. Ther Drug Monit. 2004;26(2):200-205.
Baselt RC. Disposition of Toxic Drugs and Chemicals in Man. 11th ed. Biomedical Publications; 2020.
Lowe RH, Cone EJ, Darwin WD, et al. Urine testing for cannabis: a review of the disposition of 11-nor-9-carboxy-delta-9-tetrahydrocannabinol in humans. Anal Toxicol. 2009;33(8):471-479.
Moffat AC, Osselton MD, Widdop B, eds. Clarke’s Analysis of Drugs and Poisons. 4th ed. Pharmaceutical Press; 2011.
Spannhof A, et al. Analytical methodology for the determination of cannabinoids and their metabolites in biological matrices. J Chromatogr B. 2011;879(17):1201-1210.
Musshoff F, Madea B. Review of chromatographic methods for the determination of cannabinoids in biological samples. Anal Bioanal Chem. 2006;384(1):80-94.
Caplan YH, Goldberger BA. Alternative specimens for workplace drug testing. J Anal Toxicol. 2001;25(5):396-399.
Cone EJ. Testing human hair for drugs of abuse. I. Individual dose and time dependencies of methamphetamine and amphetamine in primary and secondary hair. Forensic Sci Int. 2001;124(2-3):120-128.
Karch SB. Drug Abuse Handbook. 2nd ed. CRC Press; 2006.
Substance Abuse and Mental Health Services Administration (SAMHSA). Mandatory Guidelines for Federal Workplace Drug Testing Programs. HHS; 2017.
FAQ’s:
What is cannabis?
A psychoactive drug derived from the cannabis plant used for centuries.What is the main psychoactive chemical?
Delta-9-tetrahydrocannabinol (THC) is the primary chemical responsible for intoxicating effects.Where is THC found?
It is found primarily in resin produced by female cannabis plant buds.What are cannabis metabolic stages?
Delta-9-THC breaks down into 11-OH-THC, THC-COOH, and finally conjugates into glucuronide.How does cannabis affect the brain?
It causes euphoria, relaxation, altered perception, impaired memory, anxiety, and high-dose psychosis.What are primary testing methods?
Common laboratory testing methods include HPLC, GC-MS, and immunoassay.Which sample is most common?
Urine is the most common and trusted biological sample for drug testing.How long is urine sample stable?
It remains stable for one week at room temperature, one month refrigerated, or frozen.What is the urine reference interval?
The cutoff threshold for 11-Nor-9-carboxy-THC in urine is 15 ng/mL.What is chronic use detection window?
Chronic heavy use can be detected in urine for up to sixty to ninety days.
