Cocaine overdose may cause seizures, abnormally high body temperature and a marked elevation of blood pressure, which can be life-threatening, abnormal heart rhythms, and death. Anxiety, paranoia, and restlessness can also occur, especially during the comedown. With excessive dosage, tremors, convulsions and increased body temperature are observed. Severe cardiac adverse events, particularly sudden cardiac death, become a serious risk at high doses due to cocaines blocking effect on cardiac sodium channels. Incidental exposure of the eye to sublimated cocaine while smoking crack cocaine can cause serious injury to the cornea and long-term loss of visual acuity. Chronic
Although it has been commonly asserted, the available evidence does not show that chronic use of cocaine is associated with broad cognitive deficits. Research is inconclusive on age-related loss of striatal dopamine transporter (DAT) sites, suggesting cocaine has neuroprotective or neurodegenerative properties for dopamine neurons. Exposure to cocaine may lead to the breakdown of the blood-brain barrier.Physical side effects from chronic smoking of cocaine include coughing up blood, bronchospasm, itching, fever, diffuse alveolar infiltrates without effusions, pulmonary and systemic eosinophilia, chest pain, lung trauma, sore throat, asthma, hoarse voice, dyspnea (shortness of breath), and an aching, flu-like syndrome. Cocaine constricts blood vessels, dilates pupils, and increases body temperature, heart rate, and blood pressure. It can also cause headaches and gastrointestinal complications such as abdominal pain and nausea. A common but untrue belief is that the smoking of cocaine chemically breaks down tooth enamel and causes tooth decay.
Detection in body fluids
Cocaine and its major metabolites may be quantified in blood, plasma, or urine to monitor for use, confirm a diagnosis of poisoning, or assist in the forensic investigation of a traffic or other criminal violation or sudden death. Most commercial cocaine immunoassay screening tests cross-react appreciably with the major cocaine metabolites, but chromatographic techniques can easily distinguish and separately measure each of these substances. When interpreting the results of a test, it is important to consider the cocaine usage history of the individual, since a chronic user can develop tolerance to doses that would incapacitate a cocaine-naive individual, and the chronic user often has high baseline values of the metabolites in his system. Cautious interpretation of testing results may allow a distinction between passive or active usage, and between smoking versus other routes of administration. Field analysis
Cocaine may be detected by law enforcement using the Scott reagent. The test can easily generate false positives for common substances and must be confirmed with a laboratory test.Approximate cocaine purity can be determined using 1 mL 2% cupric sulfate pentahydrate in dilute HCl, 1 mL 2% potassium thiocyanate and 2 mL of chloroform. The shade of brown shown by the chloroform is proportional to the cocaine content. This test is not cross sensitive to heroin, methamphetamine, benzocaine, procaine and a number of other drugs but other chemicals could cause false positives.