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Gerald F. O’Malley

, DO, Grand Strand Regional Medical Center;

Rika O’Malley

, MD, Grand Strand Medical Center

Reviewed/Revised Dec 2022

Cocaine is a sympathomimetic drug with central nervous system stimulant and euphoriant properties. High doses can cause panic, schizophrenic-like symptoms, seizures, hyperthermia, hypertension, arrhythmias, stroke, aortic dissection, intestinal ischemia, and myocardial infarction. Toxicity is managed with supportive care, including IV benzodiazepines (for agitation, hypertension, and seizures) and cooling techniques (for hyperthermia). Withdrawal manifests primarily as depression, difficulty concentrating, and somnolence (cocaine washout syndrome).

Most cocaine users are episodic recreational users. However, about 25% of users meet criteria for abuse or dependence. Use among adolescents has declined slightly since 2011 (1 General reference Cocaine is a sympathomimetic drug with central nervous system stimulant and euphoriant properties. High doses can cause panic, schizophrenic-like symptoms, seizures, hyperthermia, hypertension... read more ). Availability of highly biologically active forms, such as crack cocaine, has worsened the problem of cocaine dependence. Most cocaine in the US is about 45 to 60% pure; it may contain a wide array of fillers, adulterants, and contaminants.

Most cocaine in the US is volatilized and inhaled, but it may be snorted, or injected IV. For inhalation, the powdered hydrochloride salt is converted into a more volatile form, usually by adding sodium bicarbonate, water, and heat. The resultant precipitate (crack cocaine) is volatilized by heating (it is not burned) and inhaled. Onset of effect is quick, and intensity of the high rivals that associated with IV injection. Tolerance to cocaine occurs, and withdrawal from heavy use is characterized by somnolence, difficulty concentrating, increased appetite, and depression. The tendency to continue taking the drug is strong after a period of withdrawal.

General reference

Pathophysiology of Cocaine Intoxication

Cocaine, an alkaloid present in the leaves of the coca plant, enhances norepinephrine, dopamine, and serotonin activity in the central and peripheral nervous systems by blocking the reuptake of biogenic amines.

Enhancement of dopamine activity is the likely cause of the drug’s intended effects and thus of the reinforcement that contributes to developing abuse and dependence.

Norepinephrine activity accounts for the sympathomimetic effects: tachycardia, hypertension, mydriasis, diaphoresis, and hyperthermia.

Cocaine also blocks sodium channels, accounting for its action as a local anesthetic and arrhythmogenic. Cocaine causes vasoconstriction and thus can affect almost any organ. Myocardial infarction, cerebral ischemia and hemorrhage, aortic dissection, intestinal ischemia, and renal ischemia are possible sequelae.

Onset of cocaine’s effects depends on mode of use:

  • IV injection and smoking: Immediate onset, peak effect after about 3 to 5 minutes, and duration of about 15 to 20 minutes

  • Intranasal use: Onset after about 3 to 5 minutes, peak effect at 20 to 30 minutes, and duration of about 45 to 90 minutes

  • Oral use: Onset after about 10 minutes, peak effect at about 60 minutes, and duration of about 90 minutes

Because cocaine is such a short-acting drug, heavy users may inject it or smoke it repeatedly every 10 to 15 minutes.


Symptoms and Signs of Intoxication

Acute effects

Effects of cocaine use may differ depending on mode of use. When injected or smoked, cocaine causes hyperstimulation, alertness, euphoria, a sense of increased energy, and feelings of competence and power. The excitation and high are similar to those produced by injecting amphetamines Symptoms and Signs Amphetamines are sympathomimetic drugs with central nervous system stimulant and euphoriant properties whose toxic adverse effects include delirium, hypertension, seizures, and hyperthermia... read more . These feelings are less intense and disruptive in users who snort cocaine powder.

Toxicity or overdose

Cocaine can cause damage in any organ system from vasoconstriction, hemorrhage, or enhanced coagulation.

An overdose may cause severe anxiety, panic, agitation, aggression, sleeplessness, hallucinations, paranoid delusions, impaired judgment, tremors, seizures, and delirium. Mydriasis and diaphoresis are apparent, and heart rate and blood pressure are increased. Myocardial ischemia due to cocaine use may also cause chest pain (“cocaine chest pain”), but cocaine can also cause chest pain in the absence of myocardial ischemia; the mechanism is unclear. Arrhythmias and conduction abnormalities may occur. Death may result from myocardial infarction or arrhythmias.

Binges, often over several days, lead to an exhaustion syndrome or "washed out" syndrome, involving intense fatigue and need for sleep.

Severe overdose causes a syndrome of acute psychosis (eg, schizophrenic-like symptoms), hypertension, hyperthermia, rhabdomyolysis, coagulopathy, renal failure, and seizures. Patients with extreme clinical toxicity may, on a genetic basis, have decreased (atypical) serum cholinesterase, an enzyme needed for clearance of cocaine.

People who smoke the drug may develop pneumothorax Pneumothorax Pneumothorax is air in the pleural space causing partial or complete lung collapse. Pneumothorax can occur spontaneously or result from trauma or medical procedures. Diagnosis is based on clinical... read more Pneumothorax or pneumomediastinum Pneumomediastinum Pneumomediastinum is air in mediastinal interstices. The main causes of pneumomediastinum are Alveolar rupture with dissection of air into the interstitium of the lung with translocation to... read more Pneumomediastinum , causing chest pain, dyspnea, or both. People who inhale or smoke cocaine may develop an acute pulmonary syndrome sometimes called "crack lung," which is a hypersensitivity pneumonitis (which typically includes fever, hemoptysis, and fever) that occurs after inhaling cocaine and may progress to respiratory failure. Vasospasm in the pulmonary vasculature may mimic a pulmonary embolism; pulmonary infarction may develop if the spasm is severe.

The concurrent use of cocaine and alcohol produces a condensation product, cocaethylene, which has stimulant properties and may contribute to toxicity.

Chronic effects


Because of cocaine's short half-life, the withdrawal symptoms develop quickly after the last dose in habitual users. The main symptoms of cocaine use are depression, difficulty concentrating, and somnolence (cocaine washout syndrome). Appetite is increased. Withdrawal symptoms can last for several weeks to months.

Diagnosis of Cocaine Intoxication

  • Usually a clinical diagnosis

Diagnosis of cocaine intoxication is usually made clinically. Drug levels are not measured. The cocaine metabolite, benzoylecgonine, is part of most routine urine drug screens Drug Testing Drug testing is done primarily to screen people systematically or randomly for evidence of use of one or more substances with potential for abuse. Testing may be done in the following: Certain... read more .

Treatment of Cocaine Intoxication

  • IV benzodiazepines

  • Avoidance of beta-blockers

  • Cooling for hyperthermia as needed

Toxicity or overdose

Treatment of mild cocaine intoxication is generally unnecessary because the drug is extremely short-acting. Benzodiazepines are the preferred initial treatment for most toxic effects, including central nervous system excitation and seizures, tachycardia, and hypertension. Lorazepam 2 to 3 mg IV every 5 minutes titrated to effect may be used. High doses and a continuous infusion may be required. When benzodiazepine is inadequate to achieve sedation, barbiturate or propofol may be needed. Occasionally, severely agitated patients must be pharmacologically paralyzed and mechanically ventilated to ameliorate rhabdomyolysis Rhabdomyolysis Rhabdomyolysis is a clinical syndrome involving the breakdown of skeletal muscle tissue. Symptoms and signs include muscle weakness, myalgias, and reddish-brown urine, although this triad is... read more , hyperthermia Malignant Hyperthermia Malignant hyperthermia is a life-threatening elevation in body temperature usually resulting from a hypermetabolic response to concurrent use of a depolarizing muscle relaxant and a potent,... read more , and resultant acidosis Metabolic Acidosis Metabolic acidosis is primary reduction in bicarbonate (HCO3), typically with compensatory reduction in carbon dioxide partial pressure (Pco2); pH may be markedly low or slightly... read more or multisystem dysfunction.

Hypertension that does not respond to benzodiazepines is treated with IV nitrates (eg, nitroprusside), nicardipine, or alpha-adrenergic antagonist (eg, phentolamine); beta-blockers are not recommended because they allow continued alpha-adrenergic stimulation.

Hyperthermia can be life threatening and should be managed aggressively with sedation plus evaporative cooling, ice packs, and maintenance of intravascular volume and urine flow with IV normal saline solution.

Phenothiazines are not used for sedation because they lower seizure threshold, and their anticholinergic effects can interfere with cooling.

Cocaine-related chest pain is evaluated as for any other patient with potential myocardial ischemia or aortic dissection, with chest x-ray, serial ECG, and serum cardiac markers. As discussed, beta-blockers are contraindicated, and benzodiazepines are a first-line drug. If coronary vasodilation is required after benzodiazepines are given, nitrates are used, or phentolamine 1 to 5 mg IV given slowly can be considered. Beta blockers and type Ia and Ic antiarrhythmics should be avoided for the treatment of cocaine-induced arrhythmias.


Heavy cocaine users and people who inject the drug IV or smoke it are most likely to become dependent. Light users and people who take the drug nasally or orally are at lower risk of becoming dependent. Stopping sustained use requires considerable assistance, and the depression that may result requires close supervision and treatment.

Many outpatient therapies, including support and self-help groups and cocaine hotlines, exist. Inpatient therapy is used primarily when it is required for serious physical or mental comorbidity or when outpatient therapy has repeatedly been unsuccessful.

More Information

The following English-language resources may be useful. Please note that THE MANUAL is not responsible for the content of these resources.

Drugs Mentioned In This Article

Drug Name Select Trade
Alka-Seltzer Heartburn Relief, Baros, Neut
Ativan, Loreev XR
Diprivan, Fresenius Propoven
NIPRIDE RTU , Nitropress
Cardene, Cardene IV, Cardene SR
NOTE: This is the Professional Version. CONSUMERS: View Consumer Version
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