Baclofen Facts
Depressant;
Dose and durationby route · individual sensitivity varies
Oral(mg)
Threshold< 5 mgLight10 – 20 mgCommon20 – 50 mgStrong50 – 100 mgHeavy100+ mg
Starts in 30 – 75 minLasts 8 – 14 hoursAfter-effects 6 – 12 hours
Body and dependence
- Acute toxicity
- High
- Chronic toxicity
- Low
- Physical dependence
- Moderate
- Psychological dependence
- Low
- Withdrawal
- Life-threatening · fatal · medical supervision
- Compulsive redosing
- Low
Tolerance
- Builds
- Rapid
- Fully resets after
- 10.5 days
- Carries over to
- GHB;
GBL; phenibut; other GABA-B active agents
Effectslikely at a common dose
- Perception
- none likely · 2 possible, including Vestibular distortion, Spatial disorientation
- Body
- Muscle relaxation;
Sedation; +10 possible, including Dizziness, Motor control impairment, Nausea - Thinking
- none likely · 7 possible, including Cognitive impairment, Decision impairment, Confusion
- Feeling
- none likely · 3 possible
Who shouldn't take it
Absolute
Severe renal impairment (eGFR <30); Alcohol; GHB; GBL; Opioids; Methaqualone
Relative
Sleep-disordered breathing; Seizure disorder; Psychiatric instability (active depression/suicidality); Moderate renal impairment; Pregnancy; Benzodiazepines
Combinations62 recorded
Lethal (4)
Alcohol; GHB, GBL; Methaqualone; Opioids
Dangerous (36)
Alpha-2 adrenergic receptor antagonist; Antihistamines; Antipsychotics; Benzodiazepines; Benzodiazepines, Barbiturates; Buprenorphine, Kratom; Cannabis, THC; Clonidine, Guanfacine; MDMA, Amphetamines; Stimulants; Synthetic cannabinoids; Amphetamines; Anticholinergics; Atypical antipsychotics; Buspirone; Caffeine; Cannabis; Dopamine agonists; DXM; Gabapentin, Pregabalin; Ibogaine; Ketamine, DXM, PCP; Lithium; Local anesthetics; and 12 more, see full page
Caution (13)
See full page: psychedex.org/substances/baclofen
Not graded (9)
Not listed never means safe.
Seek help immediately if
- Extreme drowsiness — can't stay awake or be roused
- Confusion, slurred speech, severe loss of coordination
- Slow, shallow, or irregular breathing
- Unconsciousness / unresponsive; limp, floppy body
- Blue lips or fingertips
- Vomiting while sedated (choking / aspiration risk)
- Cold, clammy skin; weak pulse
What to do
- Try to wake them — shout, firm sternal rub
- If unresponsive or breathing is impaired, call emergency services
- Place them in the recovery position — critical, they can choke on vomit
- Monitor breathing continuously; be ready to give rescue breaths / CPR
- Never leave them alone to "sleep it off"
- Do not give other drugs, stimulants, or more depressants
Most depressant overdoses resolve with airway protection, breathing support, and monitoring. The danger is respiratory depression and choking on vomit — sharply worse when combined with opioids or alcohol. GHB/GBL overdoses often involve sudden deep unconsciousness and may self-resolve, but airway protection is essential.
988 Suicide & Crisis LifelineFireside Project: 62-FIRESIDE
psychedex.org/substances/baclofen · Version r1 · Not medical adviceValues as of