Poisoning Due to Sedatives (Sedative Overdose)

What to do right now

1. Call 911 or your local emergency number if the person is hard to wake, breathing slowly or not breathing normally.
2. Check breathing. If they are not breathing normally, start CPR if trained.
3. Give naloxone if you have it and opioids could be involved. It will not reverse sedatives, but it is safe and can reverse the opioid part of a combined overdose.
4. Place them in the recovery position (on their side) if breathing but drowsy, to keep the airway clear if they vomit.
5. Stay with them. Do not let them "sleep it off" alone.
6. Do not give coffee, cold showers or make them vomit.
7. Collect pill bottles and note what and how much may have been taken, and when.
8. If the person is awake and alert, call Poison Help at 1-800-222-1222 (US) for advice.

How sedatives affect the body

Benzodiazepines, Z-drugs and barbiturates enhance the action of GABA, the brain's main calming chemical. At normal doses they reduce anxiety and promote sleep. In overdose, they depress brain activity further, reducing alertness, coordination and the drive to breathe. Barbiturates are more dangerous than benzodiazepines because they can directly stop breathing and depress the heart.

Alcohol, opioids, gabapentin, pregabalin, some antihistamines, muscle relaxants and some antidepressants also depress the brain. Together with sedatives, they multiply the effect. The FDA requires a boxed warning on benzodiazepines and opioids about the risks of combining them.

Symptoms

Mild to moderate

• Drowsiness and sedation
• Slurred speech
• Poor coordination, unsteadiness and falls
• Confusion and poor judgment
• Memory loss of events (amnesia)
• Blurred or double vision

Severe

• Unresponsiveness or coma
• Slow, shallow breathing or pauses in breathing
• Low blood pressure and slow heart rate (more common with barbiturates)
• Low body temperature
• Vomiting with risk of inhaling vomit
• In children, older adults and people with lung disease, effects can be severe at lower doses

Who is at higher risk

• People using sedatives together with opioids or alcohol
• Older adults, who are more sensitive and more likely to fall
• People with lung disease, sleep apnea or liver disease
• Young children who find tablets
• People with depression or a history of self-harm
• People misusing sedatives or buying unregulated pills, which may contain potent substances such as fentanyl or illicit benzodiazepines

Diagnosis

Diagnosis is based on the history and examination. Hospital teams check breathing, oxygen and carbon dioxide levels, heart rhythm (ECG), blood sugar, temperature, and test for other substances such as acetaminophen, aspirin and alcohol, because mixed overdoses are common. Urine drug screens may miss some benzodiazepines and Z-drugs.

Hospital treatment

• Supportive care: the mainstay. Oxygen, monitoring, IV fluids, and breathing support with a breathing tube and ventilator if needed.
• Naloxone if opioids may be involved.
• Activated charcoal occasionally, if the person is awake and protects their airway soon after a large ingestion.
• Flumazenil, a benzodiazepine antidote, is rarely used because it can trigger seizures, particularly in people who take benzodiazepines long term or have also taken certain other drugs.
• Treatment of complications such as aspiration pneumonia.
• Mental health assessment after intentional overdoses.
• Watching for withdrawal in people who use sedatives regularly. See benzodiazepine withdrawal.

Outlook

Most people with a benzodiazepine-only overdose recover fully within 24 to 48 hours with supportive care. Outcomes are worse with barbiturates, combined overdoses with opioids or alcohol, long periods without oxygen, and aspiration pneumonia.

Prevention

• Take sedatives exactly as prescribed, at the lowest effective dose and shortest duration.
• Do not combine sedatives with alcohol, opioids or other sedating medicines unless your doctor has specifically advised it.
• Keep medicines locked away from children and others.
• Never stop long-term benzodiazepines suddenly. Withdrawal can cause seizures. Taper with your doctor.
• Carry naloxone if you or someone you live with uses opioids.
• Get help for substance use disorder: SAMHSA's National Helpline is 1-800-662-4357 (US), free and confidential.

Frequently asked questions

What are the signs of a sedative overdose?

Signs include extreme drowsiness, slurred speech, unsteadiness, confusion, slow or shallow breathing, snoring or gurgling sounds, blue lips and being difficult or impossible to wake. Call 911 or your local emergency number immediately if someone is hard to wake or breathing slowly.

Can you overdose on benzodiazepines alone?

Benzodiazepine overdose alone is rarely fatal in healthy adults, though it can cause deep sedation and falls. The risk rises sharply when benzodiazepines are combined with opioids, alcohol or other sedatives, which together can stop breathing. Older adults and children are also at higher risk.

Why is mixing sedatives and alcohol dangerous?

Both sedatives and alcohol slow brain activity and breathing. Together, their effects add up and can cause deep unconsciousness, choking on vomit and breathing that slows or stops. Mixing them is a leading contributor to overdose deaths, even at doses that would be safe separately.

Does naloxone work for sedative overdose?

Naloxone reverses opioids, not benzodiazepines or other sedatives. However, many overdoses involve both, and street pills may contain fentanyl. If opioids could be involved, giving naloxone is safe and may save a life. Always call emergency services as well.