Cardiac complications. Acute marijuana use causes tachycardia, increases supine blood pressure, and decreases standing blood pressure, resulting in dizziness, syncope, falls, and possible injuries.20,21 Increased cardiac output and cardiac work—coupled with a decreased capacity to carry oxygen—can lead to angina or acute coronary syndrome, especially in older adults with preexisting cardiovascular disease.21 Growing evidence shows that marijuana use could lead to cardiac arrhythmias, such as atrial fibrillation.20 Long-term heavy users seem to develop tolerance to some cardiovascular effects, but blood volume overall increases, heart rate slows, and circulatory responses to exercise are diminished.18
Cognitive impairment. Chronic marijuana users might experience cognitive impairment—particularly on memory of word lists and attention tasks22—but there is debate as to whether these deficits are stable or temporary. Some studies show persistent cognitive impairments in longer-term cannabis users, even after 2 years of abstinence.22 However, most studies suggest that marijuana-associated cognitive deficits are reversible and related to recent exposure.18
Table 2
Medical complications of marijuana use
| Cardiovascular: Tachycardia; increased supine blood pressure; increased risk of myocardial infarction; atrial fibrillation |
| Pulmonary: Stinging of mouth/throat; chronic/heavy cough; increased lung infections; obstructed airways; lung cancer |
| Neurologic: Decreased performance on cognitive tasks (word lists, attention); diminished reaction times |
| Other: Decreased serum testosterone, sperm count, and sperm motility; shorter menstrual cycles; increased prolactin; suppressed activity of macrophages and natural killer cell |
Cocaine
Cocaine is the most frequent cause of drug-related death, particularly when combined with alcohol.23
Chronic nasal insufflations can cause loss of sense of smell, nosebleeds, dysphagia, hoarseness, and overall irritation of the nasal septum, which in turn can lead to chronic mucosal inflammation and rhinorrhea.24 Intravenous users often have puncture marks or “tracks,” usually on the forearms, and are predisposed to infectious diseases such as human immunodeficiency virus (HIV) and other blood-borne infections.24,25 Regular cocaine ingestion can lead to bowel gangrene because of reduced blood flow and orofacial complications.24 Asking about how your patient ingests cocaine will guide your evaluation of possible medical complications (Table 3).
Cardiac complications. Recent cocaine use is a common cause of chest pain. A 2002 survey reported that 25% of patients in urban hospitals and 13% in rural settings presenting with nontraumatic chest pain tested positive for cocaine use.26 Although cocaine can lead to ventricular fibrillation, tachycardia, and increased blood pressure, its main mechanism for inducing chest pain and myocardial infarction (MI) is coronary vasospasm, especially of diseased vessels. The acute risk of MI is increased by a factor of 24 in the first 60 minutes after cocaine use.23 Chronic use promotes thrombus formation, leading to atherosclerotic disease.23 Recurrent chest pain in a young, otherwise healthy individual could indicate cocaine abuse.
Neurologic complications. Headache is the most common neurologic complication of cocaine use. Although usually associated with intoxication or withdrawal, headaches can become chronic with chronic use.25 Reduced seizure threshold also has been reported with cocaine use, particularly in patients with cerebral lesions, and most seizures occur with first-time use. Isolated events might not require anticonvulsant therapy, although referral to a neurologist is recommended.27
Cocaine use puts individuals at higher risk for subarachnoid hemorrhage, intracerebral bleed, ischemic stroke, and transient ischemic attacks. The route of cocaine ingestion seems to influence the type of stroke: IV and intranasal use are associated with hemorrhagic stroke, and inhalation with ischemic stroke.25
Table 3
Medical complications of cocaine use
| Cardiovascular: Chest pain; 24-fold increased risk of myocardial infarction; coronary vasospasm; ventricular fibrillation; tachycardia; hypertension |
| Pulmonary: Pleuritic chest pain; chronic cough; wheezing; hemoptysis; melanoptysis (black sputum); ‘crack lung’ (fever, cough, difficulty breathing, and chest pain) |
| Gastrointestinal: Xerostomia; bruxism; decreased gastric motility; ischemic colitis; bowel ulceration, infarction, and perforation |
| Neurologic: Seizures; headaches; cerebral vasoconstriction; hemorrhagic/ischemic stroke; cerebral gray matter atrophy (especially frontotemporal lobes); dystonic reactions; akathisia; choreoathetosis (‘crack dancers’) |
| Other: Acute renal failure via rhabdomyolysis; nephrosclerosis; impaired sexual function (chronic use) |
Methamphetamine
Like many illicit substances, methamphetamine can be taken in many forms.
- “Speed,” a powder form, can be snorted or injected.
- “Base” is a powder with higher purity.
- “Ice,” also known as “crystal,” has very high purity and can be smoked, “chased” (cooked on aluminum foil and smoked), mixed with marijuana, or injected.28
Evaluate meth-abusing patients for many of the same medical complications associated with cocaine and other stimulants. Acute effects include hypertension, tachycardia, and arrhythmias; chronic effects include stroke and cardiac valve sclerosis. Pulmonary hypertension can occur when the drug is smoked (Table 4).28
Dental complications. Originally believed to result from the acidity of methamphetamine, advanced tooth decay or “meth mouth” is thought to be caused by decreased production of saliva—a consequence of increased sympathetic activity—combined with overall decreased oral intake, sugar and soft drink consumption, and poor oral hygiene. Methamphetamine abusers often experience bruxism, which exacerbates tooth decay.29