When your loved one decides to get sober, detox is often the first step — and one of the most misunderstood. Families want to know how long it will last, what to expect, and how dangerous it is. This guide answers those questions clearly.

What Is Drug Detox?

Detoxification is the process of clearing a substance from the body and managing the physical withdrawal symptoms that follow. When someone has been using regularly for an extended period, their body has adapted to the presence of the substance. Removing it causes withdrawal — a range of physical and psychological symptoms as the body readjusts.

Detox Timeline by Substance

Alcohol

• Onset: 6-24 hours after last drink
• Peak symptoms: 24-72 hours
• Duration: 5-7 days for acute symptoms; up to 2 weeks for full resolution
• Risk level: HIGH — alcohol withdrawal can cause seizures and delirium tremens (DTs), which can be fatal without medical supervision

Opioids (heroin, prescription painkillers)

• Onset: 8-24 hours after last use (short-acting); 36-48 hours (long-acting like methadone)
• Peak symptoms: 36-72 hours
• Duration: 5-10 days acute; weeks of post-acute symptoms possible
• Risk level: MODERATE-HIGH — not typically life-threatening but extremely uncomfortable; relapse risk is very high during this period

Benzodiazepines (Valium, Xanax, Klonopin)

• Onset: 1-4 days after last dose
• Peak symptoms: Day 2 onwards
• Duration: 2-4 weeks; can last months for long-term users
• Risk level: HIGH — like alcohol, benzo withdrawal can cause seizures and be life-threatening

Stimulants (cocaine, methamphetamine)

• Onset: Hours after last use
• Peak symptoms: 24-72 hours
• Duration: 1-2 weeks acute; depression and fatigue can persist for weeks
• Risk level: LOW-MODERATE physically, but significant psychological symptoms including severe depression

Cannabis

• Onset: 1-3 days
• Peak symptoms: Days 2-6
• Duration: 1-2 weeks
• Risk level: LOW — not physically dangerous, but irritability, sleep disruption, and anxiety are common

Common Withdrawal Symptoms

• Nausea, vomiting, sweating
• Anxiety, agitation, restlessness
• Muscle aches and cramps
• Insomnia
• Intense cravings
• Depression and mood instability

What Families Can Do During Detox

• Encourage medically supervised detox — never encourage unsupported home detox from alcohol or benzos
• Be present and supportive without interfering with the medical process
• Prepare for irritability and emotional volatility — this is the withdrawal, not the person
• Have aftercare plans in place before detox begins
• Remember that detox is just the beginning — rehabilitation must follow

For testing during recovery: Drug Testing Kits for Families →
For what comes after detox: What Happens in Drug Rehab →