Metamorphosis Centre for Change
Yes, some withdrawals can be fatal. Alcohol withdrawal can become life-threatening, and withdrawal from benzodiazepines and barbiturates can also be dangerous without medical supervision. Opioid and stimulant withdrawal are usually not fatal by themselves, but they can still cause serious harm. If you are thinking about stopping heavy alcohol use or sedatives, or you are already having severe symptoms, speak with a doctor first. In a medical emergency, call 911.
Why Withdrawal Can Be Dangerous
Withdrawal happens when the body has adjusted to a substance and then loses it. Symptoms range from mild, such as irritability, fatigue, sweating, trouble sleeping, and cravings, to severe, such as confusion, hallucinations, seizures, high fever, a fast heartbeat, and delirium. How severe withdrawal becomes depends on the substance, how much and how long it was used, the person's general health, any other medical or mental health conditions, and whether other substances are involved.
Because these factors are hard to judge at home, it is safer to have a clinician assess the situation before stopping. Many people underestimate their risk because they have stopped before without serious problems. Each withdrawal can be different, and a past experience does not predict the next one.
Mixing substances increases risk. Alcohol combined with sedatives, opioids, or other depressants can slow breathing and raise the danger of overdose. Withdrawal from several substances at once is harder to predict, so tell a clinician about everything you use, including over-the-counter products and cannabis.
Substance by Substance
Alcohol
Alcohol withdrawal can be life-threatening, especially after heavy, daily drinking. The most severe form is delirium tremens, often called DTs. Symptoms can include severe confusion, seizures, high blood pressure, fever, and hallucinations. Without treatment, delirium tremens can be fatal. Medical care is essential, and clinicians often use medication to reduce the risk of seizures and other severe symptoms. If you drink every day, or if you have had seizures or hallucinations during past withdrawal, do not stop abruptly on your own. Get medical advice first.
Benzodiazepines and barbiturates
Benzodiazepines, such as diazepam or alprazolam, and barbiturates act on the central nervous system. Withdrawal from them can cause seizures and other severe symptoms. It can be dangerous and, in some cases, fatal without medical supervision. A doctor may plan a gradual reduction rather than an abrupt stop. Do not stop or change these medications on your own, even if you feel fine or want to be finished. Taking extra doses to stop withdrawal can also be dangerous.
Opioids
Opioid withdrawal, which can follow heroin use or the use of prescription painkillers, is very uncomfortable. Nausea, vomiting, diarrhoea, muscle aches, and anxiety are common. It is rarely fatal by itself in otherwise healthy adults. The real risks are dehydration from vomiting and diarrhoea, and overdose after a period of reduced use. Tolerance drops during abstinence, so an amount that was once manageable can now be deadly. Anyone who uses opioids should keep naloxone on hand, and family members should know how to use it. Naloxone is an emergency medication that can reverse an opioid overdose. If someone stops breathing or cannot be woken, call 911.
Stimulants
Withdrawal from stimulants such as cocaine or methamphetamine is generally not considered life-threatening in the same way as alcohol or sedative withdrawal. The main concern is psychological. Severe depression, agitation, and suicidal thoughts can occur, and these need prompt attention. If you are having thoughts of suicide, you can call or text 988 in Canada. If you are in immediate danger, call 911.
Withdrawal can change quickly. Symptoms that seem manageable in the morning can become severe by evening, and some symptoms can continue for days or weeks. Monitoring by someone who knows what to watch for is one of the main reasons medical supervision matters.
Many people delay getting help because they are afraid of being judged, worried about legal trouble, or hoping the symptoms will pass. Those fears are understandable, but waiting can turn a manageable situation into an emergency. If you are unsure whether symptoms are serious, it is better to get checked than to wait.
Warning Signs That Need Emergency Care
Call 911 right away if someone has any of the following: a seizure; confusion, hallucinations, or agitation that is getting worse; fainting or being hard to wake; chest pain, a racing or irregular heartbeat, or trouble breathing; vomiting blood or signs of severe dehydration; a high fever with confusion; or thoughts of harming themselves or someone else.
While you wait for help, stay with the person. If they are vomiting or drowsy, keep them on their side. Do not give them more of the substance. Do not leave someone alone who is in severe withdrawal.
Ask about the plan before you begin. Find out who will monitor you, which symptoms to report, and what happens if things get worse. A good plan is written down and includes a clear emergency route, so nobody has to guess what to do at 2 a.m.
Safer Next Steps
If you are thinking about stopping, the safest first step is a conversation with a doctor or pharmacist. They can review what you use, how much, how often, your health, and any medications you take, and they can explain whether medical detox is recommended. Our medical detox program provides monitoring and medical support during withdrawal. In Ontario, you can also call Health Connect Ontario at 811 to speak with a registered nurse.
Avoid mixing substances, and avoid trying to treat yourself with medication from other sources. Tell every clinician exactly what you have been using, because that information changes the plan. To talk with our team about medical detox, call 705-429-3870 or use our contact form.
At a medical assessment, a clinician will usually ask what you use, how much, how often, when you last used, whether you have had withdrawal before, and whether you have a history of seizures, heart problems, liver disease, or mental health concerns. They may check your vital signs and ask about medications. This information helps them judge risk and decide what level of care is safest.
For some substances, a gradual reduction under medical supervision is safer than stopping suddenly. The plan is individual and changes as symptoms change. The goal is to reduce the danger while the body adjusts, not to push through symptoms alone.
Frequently Asked Questions
Can I detox at home safely?
Some people can, with medical guidance and a clear plan, but many cannot. Heavy alcohol use, sedative use, and certain other patterns carry real risks. A clinician can help you decide whether home withdrawal is reasonable for your situation.
Is opioid withdrawal dangerous?
It is very unpleasant and can be risky, mainly because of dehydration and the higher risk of overdose after reduced use. Medical support, fluids, and access to naloxone make a significant difference.
What if I already stopped and feel unwell?
If you have stopped and are having symptoms, especially confusion, seizures, hallucinations, fever, or chest pain, call 911 or go to an emergency department. If your symptoms are milder, contact a physician or Health Connect Ontario at 811 for advice.
Written by Dr. Leonard Bienenstock, Medical Director and Addictions Doctor, M.D., CCFP
Dr. Bienenstock completed medical school at McGill University and his family medicine residency at Toronto Western Hospital. He has further training in addictions medicine and psychotherapy and serves as Medical Director at Metamorphosis Centre for Change.
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