Last updated:
March 29, 2026
Cannabis is the most commonly used illicit drug in the world. Intoxication is usually an incidental finding on a urine toxicology screen.
The main active ingredient in cannabis is tetrahydrocannabinol (THC), which acts on cannabinoid receptors in the brain. Cannabinoid receptors inhibit adenylate cyclase. Cannabis has been used effectively to treat nausea and vomiting due to chemotherapy, to increase appetite in patients with AIDs, to treat chronic pain, and to reduce intraocular pressure in glaucoma.
Its long-term effects are controversial. Cannabis can cause leukopaenia (and mild immunosuppression) by binding to CB2 receptors, which are found on immune cells.
Cannabis use disorder occurs in 10% of those who use cannabis, and up to 50% of those with daily use.
- Signs and symptoms of acute intoxication
- Conjunctival injection (red eyes)
- Increased appetite (”munchies”)
- Dry mouth
- Aloofness
- Disturbances in time perception (time slows down)
- Occasional disturbances in sensory perception (rare)
- Anxiety
- Mild tachycardia
- Signs and symptoms of withdrawal
- Irritability
- Anxiety
- Restlessness
- Aggression
- Strange dreams
- Depression
- Headaches
- Sweating
- Chills
- Insomnia
- Reduced appetite
- Treatment of intoxication
- Supportive treatment
- Psychosocial intervention
- Complications of cannabis use (chronic use)
- Cannabis-induced psychotic disorder (paranoia, hallucination, and/or delusions)
- Asthma
- Chronic bronchitis
- Immnuosupression
- Cancer
Biochemistry
| ACTH | P: <80 ng/L |
| ALT | P: 5–35 U/L |
| Albumin | P: 35–50 g/L |
| Aldosterone | P: 100–500 pmol/L |
| Alk. phosphatase | P: 30–130 U/L |
| α-Amylase | P: 0–180 IU/dL |
| α-Fetoprotein | S: <10 kU/L |
| Angiotensin II | P: 5–35 pmol/L |
| ADH | P: 0.9–4.6 pmol/L |
| AST | P: 5–35 U/L |
| Bicarbonate | P: 24–30 mmol/L |
| Bilirubin | P: 3–17 μmol/L |
| BNP | P: <50 ng/L |
| CRP | P: <10 mg/L |
| Calcitonin | P: <0.1 mcg/L |
| Calcium (ionized) | P: 1.0–1.25 mmol/L |
| Calcium (total) | P: 2.12–2.60 mmol/L |
| Chloride | P: 95–105 mmol/L |
| Cholesterol | P: <5.0 mmol/L |
| VLDL | P: 0.128–0.645 mmol/L |
| LDL | P: <2.0 mmol/L |
| HDL | P: 0.9–1.93 mmol/L |
| Cortisol AM | P: 450–700 nmol/L |
| Cortisol Midnight | P: 80–280 nmol/L |
| CK ♂ | P: 25–195 U/L |
| CK ♀ | P: 25–170 U/L |
| Creatinine | P: 70–100 μmol/L |
| Ferritin | P: 12–200 mcg/L |
| Folate | S: 2.1 mcg/L |
| FSH | P: 2–8 U/L ♂; >25 menopause |
| GGT ♂ | P: 11–51 U/L |
| GGT ♀ | P: 7–33 U/L |
| Glucose (fasting) | P: 3.5–5.5 mmol/L |
| Growth hormone | P: <20 mu/L |
| HbA1C (DCCT) | B: 4–6% |
| HbA1C (IFCC) | B: 20–42 mmol/mol |
| Iron ♂ | S: 14–31 μmol/L |
| Iron ♀ | S: 11–30 μmol/L |
| Lactate (venous) | P: 0.6–2.4 mmol/L |
| Lactate (arterial) | P: 0.6–1.8 mmol/L |
| LDH | P: 70–250 U/L |
| LH | P: 3–16 U/L |
| Magnesium | P: 0.75–1.05 mmol/L |
| Osmolality | P: 278–305 mosmol/kg |
| PTH | P: 0.8–8.5 pmol/L |
| Potassium | P: 3.5–5.3 mmol/L |
| Prolactin ♂ | P: <450 U/L |
| Prolactin ♀ | P: <600 U/L |
| PSA | P: 0–4 mcg/mL |
| Protein (total) | P: 60–80 g/L |
| Red cell folate | B: 0.36–1.44 μmol/L |
| Renin (erect) | P: 2.8–4.5 pmol/mL/h |
| Renin (recumbent) | P: 1.1–2.7 pmol/mL/h |
| Sodium | P: 135–145 mmol/L |
| TBG | P: 7–17 mg/L |
| TSH | P: 0.5–4.2 mU/L |
| T4 | P: 70–140 nmol/L |
| Free T4 | P: 9–22 pmol/L |
| TIBC | S: 54–75 μmol/L |
| Triglycerides | P: 0.50–2.3 mmol/L |
| T3 | P: 1.2–3.0 nmol/L |
| Troponin T | P: <0.1 mcg/L |
| Urate ♂ | P: 210–480 μmol/L |
| Urate ♀ | P: 150–390 μmol/L |
| Urea | P: 2.5–6.7 mmol/L |
| Vitamin B12 | S: 0.13–0.68 nmol/L |
| Vitamin D | S: 50 nmol/L |
Arterial Blood Gases
| pH | 7.35–7.45 |
| PaCO₂ | 4.7–6.0 kPa |
| PaO₂ | >10.6 kPa |
| Base excess | ±2 mmol/L |
Urine
| Cortisol (free) | <280 nmol/24h |
| Hydroxyindole acetic acid | 16–73 μmol/24h |
| Hydroxymethylmandelic acid | 16–48 μmol/24h |
| Metanephrines | 0.03–0.69 μmol/mmol cr. |
| Osmolality | 350–1000 mosmol/kg |
| 17-Oxogenic steroids ♂ | 28–30 μmol/24h |
| 17-Oxogenic steroids ♀ | 21–66 μmol/24h |
| 17-Oxosteroids ♂ | 17–76 μmol/24h |
| 17-Oxosteroids ♀ | 14–59 μmol/24h |
| Phosphate (inorganic) | 15–50 mmol/24h |
| Potassium | 14–120 mmol/24h |
| Protein | <150 mg/24h |
| Protein/creatinine ratio | <3 mg/mmol |
| Sodium | 100–250 mmol/24h |
Haematology
| WCC | 4.0–11.0 ×10⁹/L |
| RBC ♂ | 4.5–6.5 ×10¹²/L |
| RBC ♀ | 3.9–5.6 ×10¹²/L |
| Hb ♂ | 130–180 g/L |
| Hb ♀ | 115–160 g/L |
| PCV ♂ | 0.4–0.54 L/L |
| PCV ♀ | 0.37–0.47 L/L |
| MCV | 76–96 fL |
| MCH | 27–32 pg |
| MCHC | 300–360 g/L |
| RDW | 11.6–14.6% |
| Neutrophils | 2.0–7.5 ×10⁹/L (40–75%) |
| Lymphocytes | 1.0–4.5 ×10⁹/L (20–45%) |
| Eosinophils | 0.04–0.44 ×10⁹/L (1–6%) |
| Basophils | 0–0.10 ×10⁹/L (0–1%) |
| Monocytes | 0.2–0.8 ×10⁹/L (2–10%) |
| Platelets | 150–400 ×10⁹/L |
| Reticulocytes | 0.8–2.0% / 25–100 ×10⁹/L |
| Prothrombin time | 10–14 s |
| APTT | 35–45 s |
Paediatric
| Pulse Rate (bpm) |
|---|
| Neonate | 140–160 |
| Infant <1yr | 120–140 |
| 1–5 years | 110–130 |
| 5–12 years | 80–120 |
| >12 years | 70–100 |
| Respiratory Rate (tachypnoea) |
|---|
| 0–2 months | ≥60/min |
| 2–12 months | ≥50/min |
| 1–5 years | ≥40/min |
| >5 years | ≥30/min |
| Blood Pressure (mmHg) |
|---|
| Term | 65/45 |
| 1 year | 75/50 |
| 4 years | 85/60 |
| 8 years | 95/65 |
| 10 years | 100/70 |
| Weight Formulas |
|---|
| 3–12 months | (a + 9)/2 kg |
| 1–6 years | 2a + 8 kg |
| >6 years | (7a − 5)/2 kg |
| Haemoglobin (g/dL) |
|---|
| Term newborn | 13–20 |
| 1 month | 11–18 |
| 2 months | 10–15 |
| 1–2 years | 10–13 |
| >2 years | 11–14 |
| MUAC (6 months–5 years) |
|---|
| Obese | >17.5 cm |
| Normal | 13.5–17.4 cm |
| At risk | 12.5–13.4 cm |
| Moderate malnutrition | 11.5–12.4 cm |
| Severe malnutrition | <11.5 cm |
| Developmental Milestones |
|---|
| Social smile | 1.5 months |
| Head control | 4 months |
| Sits unsupported | 7 months |
| Crawls | 10 months |
| Stands unsupported | 10–12 months |
| Walks | 12–13 months |
| Talks | 18 months |
| CSF WBC (/mm³) |
|---|
| Term newborn | 0–25 |
| >2 weeks | 0–5 |
