Drug Overdose Symptoms, Risk Factors, Causes, Addiction Rehab & Treatment Options

What Is an Overdose? An overdose represents a pathologic level of drug toxicity—at such a magnitude that it overwhelms normal physiological functioning. Depending on what drug a person has taken, drug overdose symptoms vary. It is not always easy to discern drug overdose symptoms from mere drug use, because some of the drug’s innate effects—for […]

What Is an Overdose?

An overdose represents a pathologic level of drug toxicity—at such a magnitude that it overwhelms normal physiological functioning. Depending on what drug a person has taken, drug overdose symptoms vary. It is not always easy to discern drug overdose symptoms from mere drug use, because some of the drug’s innate effects—for example, pupillary miosis or constriction with opioids—will be present in both situations.

People may not realize they are experiencing an overdose, especially if they are heavily under the influence of that drug. Some general symptoms associated with various overdose states include severe chest pain, seizures, severe headaches, difficulty breathing, delirium, extreme agitation, or anxiety.

In addition to these symptoms, other signs may include:

Drug Overdose Symptoms
An overdose represents a pathologic level of drug toxicity—at such a magnitude that it overwhelms normal physiological functioning.
  • Passing out or an unresponsive loss of consciousness
  • Skin color changes (e.g., pallor or bluish tint to skin if a respiratory depressant was used; ruddy or flushed after cardiovascular overstimulation).
  • Deviations from normal body temperature (e.g., hyperthermia/hypothermia)
  • Abnormal breathing
  • Fast, slowed, or irregular pulse

Especially in the context of illicit substance use, it is difficult for individuals to know exactly how much of a drug they are injecting, snorting, smoking, or taking orally. The risk of overdose may be particularly high when intravenous drug use is at play. In these settings, the effects of the injected drug take action much more quickly than if the drug were swallowed. Those who choose to inject drugs, such as heroin, are often looking for a stronger high than they would otherwise get.

Drug overdose symptoms might happen accidentally for a variety of reasons, such as taking a regular dose after tolerance has lowered, taking a stronger dose than the body is accustomed to, or combining substances of abuse. While some people do overdose intentionally, the majority of overdoses are unintended. Overdose is a medical emergency, and prompt medical attention can help prevent lasting health consequences or death or lasting health consequences. Many states have passed “Good Samaritan” laws that legally protect the person who suffered the overdose, as well as those who call 911 to report the emergency.

Overdose Risk Factors

If you abuse any substance, there is always a risk of overdosing. However, certain actions and conditions may further increase that risk, and it is important to be aware of them to reduce the chance of a person overdosing, these factors include:

  • Significant physiologic dependence on the drug
  • Prior overdose(s)
  • Abusing multiple substances, including alcohol
  • Taking a large amount of the substance at once
  • Dropping out of substance abuse treatment
  • Gradually increasing the dose of the substance over time
  • A reluctance to seek emergency help when needed
  • Intravenous drug use
  • Being recently released from prison
  • Previous suicide attempts
  • Resuming drug use after a period of abstinence
  • Low level of physical tolerance

Tolerance refers to the state that occurs when your body has become accustomed to the presence of the drug, so it requires increased amounts or more frequent doses of the drug to achieve the kind of high you previously got with a smaller dose. If you continue to increase your dose or take the drug more frequently, you may have a higher risk of overdosing.

Tolerance may also influence overdose risk in another way. For instance, people with a history of chronic or heavy substance abuse may develop considerable tolerance to the effects of a drug, allowing them to take more than someone who is “drug naïve,” or has less of a history with the substance. Following attempts to quit the drug or any period of abstinence, tolerance may abate in the drug-free interim. Should that person suddenly return to using the drug, especially in doses that they may have once been accustomed to, an overdose may be more likely.

Prescription Drug Overdose Causes

The cause of a drug overdose is either accidental overuse or intentional misuse. Accidental overdoses result from either a young child or an adult with impaired mental abilities swallowing a medication left within their grasp. An adult (especially seniors or people taking many medications) can mistakenly ingest the incorrect medication or take the wrong dose of a medication. Purposeful overdoses are for the desired effect, either to get high or to harm oneself.

  • Young children may swallow drugs by accident because of their curiosity about medications they may find. Children younger than age 5 (especially age 6 months to 3 years) tend to place everything they find into their mouths. Drug overdose symptoms in this age group are generally caused when someone accidentally leaves a medication within the child’s reach. Toddlers, when they find medications, often share them with other children. Therefore, if you suspect an overdose in one child while other children are around, those other children may have taken the medication, too.
  • Adolescents and adults are more likely to overdose on one or more drugs in order to harm themselves. Attempting to harm oneself may represent a suicide attempt. People who purposefully overdose on medications frequently suffer from underlying mental health conditions. These conditions may or may not have been diagnosed before.
Drug Overdose Symptoms
The cause of a drug overdose is either accidental overuse or intentional misuse.

Illicit Drug Overdose Symptoms

Different drugs are associated with various drug overdose symptoms. Some signs of overdose for the following types of drugs include:

  • Central nervous system (CNS) depressants: shallow breathing, weak pulse, clammy skin, coma, death from respiratory arrest
  • Hallucinogens: psychotic features, agitation, delirium
  • Inhalants: marked CNS depression, loss of consciousness, stupor or coma, arrhythmia, sudden death
  • Marijuana: profound drowsiness, unsteady gait, vomiting, tachycardia, agitation, psychosis
  • Opioids: depressed level of consciousness, respiratory depression/arrest, cold/clammy skin, cyanosis (bluish skin), markedly constricted pupils (dilated if anoxic brain injury has occurred)
  • Stimulants: hyperthermia, tachycardia, hypertension, arrhythmia, agitation, hallucinations and other psychotic features, seizures, cardiovascular emergencies

Prescription Drug Overdose Symptoms

Drugs have effects on the entire body. Generally, in an overdose, the effects of the drug may be a heightened level of the therapeutic effects seen with regular use. In overdose, side effects become more pronounced, and other effects can take place, which would not occur with normal use. Large overdoses of some medications cause only minimal effects, while smaller overdoses of other medications can cause severe effects, possibly death.

A single dose of some medications can be lethal to a young child. Some overdoses may worsen a person’s chronic disease. For example, an asthma attack or chest pains may be triggered.

  • Problems with vital signs (temperature, pulse rate, respiratory rate, blood pressure) are possible and can be life threatening. Vital sign values can be increased, decreased, or completely absent.
  • Sleepiness, confusion, and coma (when someone cannot be aroused) are common and can be dangerous if the person breathes vomit into the lungs (aspirated).
  • Skin can be cool and sweaty, or hot and dry.
  • Chest pain is possible and can be caused by heart or lung damage. Shortness of breath may occur. Breathing may get rapid, slow, deep, or shallow.
  • Abdominal pain, nausea, vomiting, and diarrhea are possible. Vomiting blood, or blood in bowel movements, can be life threatening.
  • Specific drugs can damage specific organs, depending on the drug.

What Should Be Done If A Person Is Showing Drug Overdose Symptoms?

If you suspect that you or someone nearby is suffering from a drug or alcohol overdose, call 911 immediately. Do not leave the person alone; stay with them until medical professionals arrive.

If you witness an overdose, and the person has passed out, they should be placed on their side just in case they vomit. This should help prevent any choking accidents, should they occur. The person should also not eat or drink anything. If friends know what substances were taken, they should report this to emergency responders so appropriate treatment can be given.

If the person has consumed too much alcohol, do not attempt to make them drink coffee or put them in a cold shower. These longstanding home “treatments” for alcohol intoxication do not help to sober the person up. They can lead to accidents or injuries.

In many cases of substance overdose, including alcohol poisoning, immediate treatment can save lives. If it isn’t received, the following could occur:

  • The person could vomit and then aspirate or choke on the vomit.
  • The person could develop a pathological heart rhythm, or the heart could even stop.
  • The person could experience slowed or irregular breathing, or breathing could stop altogether.
  • Body temperature may drop.
  • If the person vomits repeatedly, severe dehydration may occur, which may precipitate other complications, including seizures.
  • Should respiratory arrest occur, lasting anoxic brain damage and other organ injury may occur; the risk of death is very high.

Users may feel that there is safety in numbers, believing that if something goes wrong while using drugs that the other people present will assist them as needed. However, even at parties or other group situations, friends or acquaintances may fear consequences from law enforcement if they call 911. As a result, some people may simply leave the scene if they notice someone is having drug overdose symptoms.

Are Drug Overdose Symptoms Signs That Treatment Is Necessary?

In many instances, accidental overdose is a clear sign that treatment is necessary. That being said, someone can overdose the first time they use a substance, and in these cases, the person may not necessarily meet the criteria for substance use disorder—or addiction—and might not require the full range of addiction treatment services. Even in those instances, education on substance use and abuse is recommended, though the overdose itself will likely serve as the biggest deterrent to future drug use.

It remains, though, that many people who overdose have a history of substance abuse and/or addiction. For these people, comprehensive treatment that includes medical detox and therapy could be very beneficial. Treatment should address the underlying reasons that led to substance abuse in the first place as well as any co-occurring medical or mental health issues. With assistance, recovery is within reach, ensuring a future that is free of overdose and related health issues.

Good Samaritan Laws When Witnessing Drug Overdoses

Under Good Samaritan laws, if people realize that someone is experiencing an overdose, they should call 911 right away and report the emergency. Once they do so, and emergency responders give medical assistance to the person in need, they are given limited protection from prosecution for possession of drugs and/or alcohol. Though the laws vary somewhat by state, the person who overdosed may receive the same immunity for possession of small amounts of illicit substances. While this limited immunity protects those who possess or use alcohol or drugs, it won’t protect them from other drugs- and non-drug-related crimes.

Drug Overdose Symptoms
In many instances, accidental overdose is a clear sign that treatment is necessary.

Additionally, The Drug Policy Alliance points out that only the person witnessing the drug overdose and the person suffering from the overdose are protected under the Good Samaritan law. In most cases, they are protected from being under the influence, simple drug possession, and possession of drug paraphernalia.

Many believe that Good Samaritan immunity laws have the potential to save lives, reducing fear around calling for professional medical help. Generally, in cases of overdose, 1-3 hours may pass between the time the person takes the drug and death. If emergency responders can reach the person suffering from an overdose during this window, the person is more likely to survive via lifesaving treatment.

Reclaim Your Life From Drug Overdose Symptoms

Learning how to spot drug overdose symptoms can save you or a loved one from dangerous outcomes such as overdose itself or premature death. Substance abuse disorder is a condition that can cause significant health, social, and economic problems that should not be taken lightly. We Level Up Washington treatment center can provide you, or someone you love, treatment with professional and safe care. Feel free to call us to speak with one of our counselors. We can inform you about this condition by giving you relevant information. Our specialists know what you are going through. Please know that each call is private and confidential.

We Level Up Washington Mental Health Center: Primary Mental Health Treatment with Secondary Co-Occurring Treatments

The We Level Up Washington primary mental health center stands ready to help. Offering secondary treatment programs for underlying conditions like drug addiction and drug overdose frequently fuels harmful behaviors. Taking that first step to get the professional support you need can be life-transforming.

We know how mental health disorders and secondary co-occurring substance abuse diagnoses directly affect one another. The We Level Up Washington treatment center provides recovery programs through science-based mental health treatments that can help you feel better. Call us now for a free mental health evaluation! 

Inpatient medical detox and residential primary addiction treatment may be available at affiliated facilities at other We Level Up Treatment Centers locations beyond the Washington treatment facility.


[1] National Institute on Drug Abuse. (2017). Overdose Death Rates.

[2] Centers for Disease Control and Prevention. (2016). Morbidity and Mortality Weekly Report (MMWR): Increases in Drug and Opioid Overdose Deaths — United States, 2000–2014.

[3] U.S. National Library of Medicine: Medline Plus. (2016). Drug use first aid.

[4] We Level Up Treatment Center – International Overdose Awareness Day