A drug overdose is the accidental or intentional use of a drug or medicine inan amount that is higher than normally used. All drugs have the potential tobe misused, whether legally prescribed by a doctor, purchased over the counter at the local drug store, or bought illegally on the street. Taken in combination with other drugs or alcohol, even drugs normally considered safe can cause death or serious long-term consequences.
Children are particularly at risk for accidental overdose and account for over 1 million poisonings each year. People who suffer from depression and who have suicidal thoughts are also at high risk for drug overdose. Accidental overdose may even result from misuse of prescription medicines or commonly usedmedications like pain relievers and cold remedies.
Symptoms of overdose differ depending on the drug taken. Some of the most common drugs involved in overdoses are acetaminophen (i.e., Tylenol); anticholinergic drugs, which block the action of the neurotransmitter acetylcholine (such as atropine, scopolamine, belladonna, antihistamines, and antipsychotic agents); antidepressant drugs such as amitriptyline, desipramine, and nortriptyline); cholinergic drugs, which stimulate the parasympathetic nervous system(carbamate, pilocarpine, etc.); cocaine and crack cocaine; depressant drugs (tranquilizers, antianxiety drugs, sleeping pills); digoxin, a drug used to regulate the heart; narcotics or opiates (heroin, morphine, codeine, etc.); andsalicylates (aspirin).
Diagnosis of a drug overdose may be based on the symptoms that develop, although the drug may do extensive damage to the body before significant symptomsdevelop. If the patient is conscious, he or she may be able to tell what drugs and amounts are involved. The patient's recent medical and social history may also help in a diagnosis. For example, a list of medications that the patient takes, whether or not he or she recently consumed alcohol, and whether the patient has eaten in the last few hours before the overdose can be valuablein assessing the situation.
Different drugs have varying effects on the body's crucial acid/base balanceand on certain elements in the blood such as potassium and calcium. Blood tests are useful for detecting changes in body chemistry that may give clues asto what drugs were taken. Blood can also be screened for various drugs in thesystem. Once the overdose drug is identified, blood tests can monitor how fast the drug is clearing out of the body. Urine tests can also screen for somedrugs and detect changes in the body's chemistry. Blood and urine tests mayshow if there is damage to the liver or kidneys as a result of the overdose.
If a drug overdose is discovered or suspected and the person is unconscious,having convulsions, or not breathing, call for emergency help immediately. Ifthe person who took the drug is not having symptoms, call a poison control center immediately anyway. Providing as much information as possible to the poison control center can help determine what the next course of action shouldbe.
Emergency medical treatment may include:
- Assessment of the patient's airway and breathing to make sure that the trachea, the passage to the lungs,is not blocked. A tube may be inserted through the mouth and into the tracheato help the patient breath. This procedure is called intubation.
- Assessment of the patient's heart rate, blood pressure, body temperature, and other physical signs. These might indicate the effects of the drug.
- Blood and urine sample collection. Laboratories will test these for the presenceof the suspected overdose drug and any other drugs or alcohol that might bepresent.
- Elimination of the drug that has not yet been absorbed. Vomiting may be induced using ipecac syrup or other substances that cause vomiting. Ipecac syrup should not be given to patients who overdosed with tricyclicantidepressants, theophylline, or any drug that causes a significant change in mental status. If a patient vomits while unconscious, there is a serious risk of choking. Activated charcoal is also sometimes given to absorb the remaining drugs.
- Gastric lavage, or "pumping" the stomach. For this procedure a flexible tube is inserted through the nose, down the throat, and into the stomach. The contents of the stomach are then suctioned out through the tube. A solution of saline (salt water) is injected into the tube to rinse outthe stomach. This solution is then also suctioned out.
- Medication tostimulate urination or defecation. This may flush any remaining drug out of the body faster.
- Intravenous (IV) fluids. An intravenous line (a needle inserted into a vein) may be put into the arm or back of the hand. Fluids,either sterile saline (salt water solution) or dextrose (sugar-water solution) can be administered through this line. Increasing fluids can help to flushthe drug out of the system and reestablish balance of fluids, acids/bases, and minerals in the body.
- Hemodialysis (a form of blood "washing") to filter some drugs out of the blood.
Antidotes are available for some drug overdoses. An antidote is another drugthat counteracts or blocks the overdose drug. For example, an acetaminophen overdose can be treated with an oral medication, N-acetylcysteine (Mucomyst),if the level of acetaminophen found in the blood is extremely high. Naloxoneis an antinarcotic drug that is given to counteract narcotic poisoning. Nalmefen or methadone may also be used. Psychiatric evaluation may be recommendedif the drug overdose was deliberate.
While many victims of drug overdose recover without long-term effects, therecan be serious consequences. Some drug overdoses cause the failure of major organs like the kidneys or liver, or failure of whole systems like the respiratory or circulatory systems. Patients who survive drug overdose may need kidney dialysis, kidney or liver transplant, or ongoing care as a result of heart failure, stroke, or coma. Death can occur in almost any drug overdosesituation, particularly if treatment does not begin immediately.
To protect children from accidental drug overdose, all medications should bestored in containers with child-resistant caps. All drugs should be out of children's sight and reach--preferably in a locked cabinet. Prescription medications should be used according to directions and only by the person whose name is on the label. Threats of suicide need to be taken seriously and appropriate help sought for people with depression or other mental illness that may lead to suicide.
About 500,000 cases of overdose of tricyclic antidepressants (TCAs) are reported in the United States each year. Although selective serotonin reuptake inhibitors (SSRIs) are the drugs of choice for treating depression, TCAs are still widely used. Since the lethal dose is only eight times the therapeutic dose, TCAs pose a significant risk for patient overdose. In 1999, Nursingmagazine published a report showing that 25% to 50% of patients admitted tohospitals for drug overdose had TCA toxicity. Patients admitted with TCA toxicity are prone to breathing difficulties and episodes of irregular heartbeatthat can be life-threatening up to five or six days after the overdose. Patients who have overdosed on TCAs are also at risk of developing seizures and going into a coma. It is important that such patients receive psychiatric intervention in addition to medical monitoring and that counseling be extended tothe patient's family as well.
Patients receiving psychiatric services are also at risk for overdosing on second-generation antipsychotic medicines such as Zyprexa. In the first year Zyprexa was placed on the market for treatment of schizophrenia, the manufacturer reported 72 overdoses, with two that resulted in death. Some patients havereported "hearing" a delusional command to take all of their medication at once. In this limited sampling, many patients responded very well to early administration of activated charcoal that quickly helps in diluting the effect of Zyprexa.
In a 1999 report on teenage suicide, The Education Digest stated thatit is a myth that most adolescents who commit suicide do so by drug overdose.Figures gathered in 1994 show that guns accounted for 67% of adolescent suicide.
Users of illicit drugs account for many drug overdoses. Often young people gravitate to the so-called "party drugs:"
- Crystal methamphetamine (meth), a highly addictive amphetamine that can cause paranoia, hallucinations andliver damage.
- Ecstasy (MDMA), an amphetamine derivative that is oftenmixed with other drugs.
- Ephedrine, an over-the-counter "speedy" substance often found in cold remedies.
- Gamma hydroxybutrate (GHB), a steroid that was sold over the counter in health food stores before it was banned.
- Lysergic acid diethylamide (LSD or acid), a strong hallucinogen.
- Monoamine oxidase (MAO) inhibitors, antidepressants.
- Ketamine(Special K), anesthetic for animals.
- 2CB, a mild psychedelic formula.
"Polydrugs" are often the fashion for those on the "club scene" of electronicdance music and "rave" parties. In a party atmosphere, an individual might try a variety of drugs, risking an overdose of unknown proportions, since recreational drugs don't come in standardized doses. In 1999, electronic music fans in the United States died in a variety of accidents presumed to be drug-related: a car crash in the mountains after a rave party, a fatal stabbing, a fall in Eagle Mountain, California, and overdoses in hotel rooms. Rave fans claim that drugs are used in many different settings, not just at rave parties,and they point out that alcohol-related overdoses far outnumber overdoses connected with rave events. After several well-publicized deaths of teenagers at clubs in New York in 1999, nightclubs fearing lawsuits started cracking down on drug use on the premises.
Great Britain's statistics show that half a million people use Ecstasy each weekend, often in combination with other drugs. The polydrug pattern is very common with Ecstasy, making it difficult to pinpoint what role Ecstasy plays in overdose.
Britain's study of intravenous (IV) drug users is more precise, showing thataccidental overdose is the most frequent cause of death in this population. Intravenous drug users die at a rate 10 times higher than their peers. Studiesshow that most people who die of drug overdose also have high levels of benzodiazepines (e.g., sedatives and antianxiety agents) and/or alcohol in the body. Despite these risks, most drug overdoses are not fatal. One survey foundthat 86% of addicts had witnessed an overdose but for a variety of reasons, most were reluctant to seek help. British clinicians tried to set up criteriato separate deliberate suicide attempts from accidental overdoses but found there were some instances in which the IV drug user's state of mind was ambiguous and it was impossible to determine exactly what had happened. If a drug overdose is deliberate and the patient refuses treatment, then the emergency room staff faces an array of ethical questions regarding the patient's competence and autonomy.
In many Western countries, a public health approach to drug use and drug overdose is under consideration. Some critics charge that the United States has closed so many treatment centers that it is difficult for people who misuse drugs to get treatment. During the Nixon administration, a public health approach was attempted, with a large investment in addiction treatment. The rates of hospital emergency-room visits, overdose deaths and heroin-related crime all went down. Another approach is the legalization or decriminalization of drugs. Critics fear that deaths by drug overdose would increase if drugs were freely available.