Drug Overdose Response: Know the Signs


All drugs have the potential to be 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 usually considered safe can cause death or serious long-term consequences. 

Children are particularly at risk for accidental overdose, accounting for over one million poisonings each year from drugs, alcohol, and other chemicals and toxic substances. People who suffer from depression and who have suicidal thoughts are also at high risk.

What are the causes and symptoms of drug overdose?

Accidental drug overdose may be the result of misuse of prescription medicines or commonly used medications like pain relievers and cold remedies. Symptoms differ depending on the drug taken. Some of the drugs typically involved in overdoses are listed below, along with associated symptoms and outcomes.

Acetaminophen is the generic name for the commonly used pain reliever, Tylenol. Overdose of this drug causes liver damage with symptoms that include loss of appetite, tiredness, nausea and vomiting, paleness, and sweating. 

The next stage of symptoms indicates liver failure. These include abdominal pain and tenderness, swelling of the liver, and abnormal blood tests for liver enzymes. 

In the last stage of this poisoning, liver failure advances, and the patient becomes jaundiced, with yellowing of the skin and whites of the eyes. Ultimately, an acetaminophen-induced overdose may result in kidney failure, bleeding disorders, and encephalopathy (swelling of the brain).

Anticholinergic drugs, drugs that block the action of acetylcholine, a neurotransmitter- like atropinescopolaminebelladonnaantihistamines, and antipsychotic agents cause the skin and moist tissues, such as the mouth and nose, to become dry and flushed. Dilated pupils, an inability to urinate, and mental disturbances are also symptoms. Severe toxicity can lead to seizures, abnormal heart rhythms, extremely high blood pressure, and coma.

Antidepressants including amitriptyline (Elavil)desipramine (Norpramin), and nortriptyline (Pamelor) may cause irregular heart rate, vomiting, low blood pressure, confusion, and seizures. An overdose of antidepressants also causes symptoms similar to those seen with anticholinergic drug overdoses (see anticholinergic drugs)

Depressant drugs– tranquilizersanti-anxiety drugssleeping pills– are associated with various side effects. These may include sleepiness, slowed or slurred speech, difficulty walking or standing, blurred vision, impaired ability to think, disorientation, and mood changes. Overdose symptoms can include slowed breathing, low blood pressure, stupor, coma, shock, and death.

Narcotics, or opiates, are drugs like heroin, morphine, and codeine. Clonidine and diphenoxylate (Lomotil) are also in this category. Overdose with opiate drugs causes sleepiness, low blood pressure, slowed heart rate, and slowed breathing. Pinpoint pupils, where the black centers of the eyes become smaller than usual, are common in opiate overdoses. However, if other drugs are taken simultaneously with opiates, they may counteract this effect on the pupils. A serious risk is that the patient will stop breathing.

How is drug overdose diagnosed?

Diagnosis of a drug overdose may be symptom-based; however, the drug may do extensive damage to the body before significant symptoms develop. If the patient is conscious, she/he may be able to say what drugs she/he took and in what amounts. The patient’s recent medical and social history may also help in a diagnosis. This may include a list of medications that the patient takes, whether or not the patient recently consumed alcohol, and even if the patient has eaten in the last few hours before the overdose. This information can be valuable in determining what drug the patient took and how fast it will be absorbed into the system.


Different drugs have varying effects on the body’s acid/base balance and certain blood elements like potassium and calcium. Medical professional may use blood tests to detect changes in body chemistry that may give clues to what drugs the patient took. Doctors may also screen blood for various drugs in the system. Once doctors identify an overdose drug(s), blood tests can monitor how fast the patient’s body clears the drug out of the system. Urine tests can also be administered to screen for some drugs and detect changes in the body’s chemistry. Blood and urine tests may also show damage to the liver or kidneys due to the overdose.

What are the treatments available for drug overdose?

If a drug overdose is discovered or suspected, and the person is unconscious, having convulsions, or is not breathing, call for emergency help immediately. If the person who took the drug is not having symptoms, do not wait to see if symptoms develop: call a poison control center immediately. Providing as much information as possible to the poison control center can help determine the next course of action.

The poison control center, paramedics, and emergency room staff will want to know:

  • What drug(s) did the patient take, and can you locate the drug’s container?
  • How much of the drug did the patient take?
  • When did the patient take the drug?
  • Was the drug taken with alcohol or any other medicines or chemicals?
  • What is the age of the patient?
  • What symptoms is the patient experiencing?
  • Is the patient conscious?
  • Is the patient breathing?

The poison control center may recommend trying to get the patient to vomit. A liquid called ipecac syrup, which is used to induce vomiting, is available at pharmacies without a prescription. Pediatricians may recommend that families keep ipecac syrup on hand in households with children. Please note that you should only use this medication on the advice of a medical professional, and you should not induce vomiting if the patient is unconscious.

Emergency medical treatment may include:

  • Intubation– An assessment of the patient’s airway and breathing to ensure that the trachea, the passage to the lungs, is not blocked. If necessary, a tube may be inserted through the mouth and into the trachea to help the patient breathe. 
  • An assessment of the patient’s heart rate, blood pressure, body temperature, and other physical signs may identify the effects of the drug.
  • Blood and urine samples may be collected to test for the suspected overdose drug and any other drugs or alcohol that might be present.
  • If the patient’s body has not yet absorbed the drug, medical professionals may attempt to eliminate it. For this, ipecac syrup or other drugs may be used to induce vomiting. Keep in mind that ipecac syrup should not be given to patients who overdosed with tricyclic antidepressantstheophylline, or any drug that causes a significant change in mental status; if a patient vomits while unconscious, there is a severe risk of choking.
  • Gastric lavage or washing out the stomach may be attempted. For this procedure, doctors insert a flexible tube through the nose, down the throat, and into the stomach. Doctors suction out the stomach contents through the tube, and a saline solution (saltwater) is injected into the tube to rinse out the stomach. Doctors then suction out this saline solution. Doctors commonly use this process to pump a patient’s stomach. 
  • Sometimes, doctors use activated charcoal to absorb the drug.
  • Medical professionals may also use medication to stimulate urination or defecation to flush the excess drug out of the body faster.
  • Doctors may also give patients 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 (saltwater solution) or dextrose (sugar water solution), can be administered through this line. Increasing fluids can help flush the drug out of the system and to re-establish the balance of fluids and minerals in the body. Doctors may need to correct the body’s pH (acid/base balance) by administering electrolytes like sodium, potassium, and bicarbonate through this IV line. If doctors need to administer drugs quickly, these can be injected directly into the IV line.
  • Doctors may also utilize hemodialysis, a process that circulates blood out of the body-pumped through a dialysis machine- and then introduces it back into the body. This process can be used to filter some drugs out of the blood. It may also be used temporarily or long-term if the kidneys become damaged due to the overdose.
  • Antidotes are available for some drug overdoses. An antidote is another drug that counteracts or blocks the overdose drug. For example, an acetaminophen overdose can be treated with oral medication, such as N-acetylcysteine (Mucomyst), if acetaminophen in the blood is extremely high. Another possible antidote is Naloxone, an anti-narcotic drug that is given to counteract narcotic poisoning. Nalmefen or methadone may also be used as antidotes. 
  • Finally, medical professionals might recommend a psychiatric evaluation if the drug overdose was deliberate. 

What should I do if someone is overdosing?

Watch our Overdose Rescue Training Video on YouTube Here. 

For more information visit our Fentanyl page and our Naloxone page

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