Emergency Medicine Hub / Toxicology & Environmental • 3 min read • 4 sections

Acute Withdrawal Syndromes & Substance Use Disorders

Comprehensive emergency evaluation and protocolized management of acute withdrawal syndromes and substance use disorders: Opioid Withdrawal pathophysiology, Clinical Opiate Withdrawal Scale (COWS) stratification, emergency department Buprenorphine-Naloxone induction protocols, and prevention of precipitated withdrawal; life-threatening Gamma-Hydroxybutyrate (GHB) and Baclofen withdrawal syndromes presenting with refractory hyperadrenergic delirium; Sedative-Hypnotic (benzodiazepine and barbiturate) withdrawal seizures and phenobarbital protocols; and Cannabinoid Hyperemesis Syndrome (CHS: cyclic vomiting, compulsive hot showers, topical capsaicin, and haloperidol).

Resuscitation Quick Actions • First 2 Minutes

High-Acuity

COWS Induction Threshold

Clinical Opiate Withdrawal Scale (COWS) >= 8-12 is MANDATORY before administering first dose of Buprenorphine (prevents precipitated withdrawal)

ED Buprenorphine Dosing

Initial dose: Buprenorphine/Naloxone 4-8 mg sublingually; reassess in 60 min and administer additional 8-16 mg (total target 16-24 mg on Day 1)

Precipitated Withdrawal Rescue

If precipitated withdrawal occurs: DO NOT stop buprenorphine! Administer high-dose buprenorphine (8-16 mg SL) to overcome receptor displacement + Clonidine + Ketamine

GHB/Baclofen Delirium

Severe autonomic instability, tremors, paranoia, auditory/visual hallucinations: treat with massive IV Diazepam (20-40 mg q15min) or Propofol infusion

Baclofen Pump Failure

Malfunction or catheter kink of intrathecal pump causes life-threatening GABA-B withdrawal: give oral Baclofen 20 mg PO q6h or Cyproheptadine, and stat neurosurgery

Cannabinoid Hyperemesis (CHS)

Cyclic vomiting + compulsive hot bathing: standard antiemetics fail -> Apply Topical 0.075% Capsaicin cream to abdomen PLUS Haloperidol 2.5-5 mg IV

Bottom-Line Clinical Pearl

In acute opioid withdrawal, initiating Buprenorphine/Naloxone in the emergency department dramatically reduces all-cause mortality and stabilizes patients, but the timing is inviolable: **NEVER initiate Buprenorphine until the patient is in active, moderate withdrawal with a COWS score >= 8 to 12**! Administering buprenorphine (a high-affinity partial mu-agonist) while full agonists (fentanyl, heroin, oxycodone) remain bound displaces them, precipitating sudden, agonizing withdrawal. In GHB and Baclofen withdrawal, patients experience profound autonomic storm and delirium that is **notoriously refractory to standard benzodiazepines**: escalate rapidly to massive doses of IV Diazepam, continuous Propofol infusions, or reinstitution of Baclofen to prevent fatal hyperthermia and rhabdomyolysis.

1. Opioid Withdrawal: The Clinical Opiate Withdrawal Scale (COWS)

Chronic opioid exposure downregulates endogenous mu-opioid receptors and upregulates adenylate cyclase and central noradrenergic output from the locus coeruleus. Abrupt cessation removes inhibitory tone, triggering massive autonomic noradrenergic hyperactivity: yawning, rhinorrhea, lacrimation, piloerection ('cold turkey'), pupillary dilation (mydriasis), severe cramping, explosive diarrhea, and intense craving. The COWS score quantifies withdrawal severity:

COWS Clinical Parameter	Scoring Range & Objective Findings	Withdrawal Severity Category
Resting Heart Rate	0 = <= 80 bpm; 1 = 81-100; 2 = 101-120; 4 = > 120 bpm	Total Score Stratification: - 5 to 12 Points: Mild withdrawal - 13 to 24 Points: Moderate withdrawal - 25 to 36 Points: Moderately severe - > 36 Points: Severe withdrawal.
Gastrointestinal Upset	0 = None; 1 = Stomach cramps; 2 = Nausea/loose stool; 3 = Vomiting/diarrhea; 5 = Multiple vomiting/diarrhea episodes	Objective evidence (diarrhea/vomiting) carries highest point values.
Sweating & Piloerection	0 = None; 1 = Flushed/moist; 2 = Diffuse beads of sweat; 3 = Sweat streaming down face; 3 = Piloerection visible on skin	Piloerection (goosebumps) is an involuntary, objective physical sign.
Pupil Size & Tremor	0 = Normal; 1 = Slightly dilated; 2 = Moderately dilated; 5 = Extremely dilated (rim of iris only); Tremor 0-4	Direct bedside penlight examination.

2. Emergency Department Buprenorphine Induction Protocol

Buprenorphine is a high-affinity partial mu-opioid agonist and kappa-opioid antagonist. Initiating Buprenorphine/Naloxone (Suboxone) in the ED doubles 30-day treatment retention and reduces overdose mortality. To avoid precipitated withdrawal, follow the protocolized timeline:

Step/Phase	Clinical Requirement & Dosing	Mechanism & Management of Pitfalls
Step 1: Verify Withdrawal Threshold	Confirm patient has reached active, moderate withdrawal: - COWS Score >= 8 to 12 - Patient exhibits objective physical signs (dilated pupils, sweating, diarrhea, piloerection).	THE PRECIPITATED WITHDRAWAL HAZARD: Buprenorphine has an extraordinarily high receptor affinity ($K_i \approx 0.2$ nM) that displaces full agonists (fentanyl, heroin). Because buprenorphine has lower intrinsic efficacy, displacing a full agonist suddenly drops mu-receptor activation, precipitating instant, agonizing withdrawal!
Step 2: Initial Test Dose	Administer Buprenorphine/Naloxone 4 to 8 mg sublingually (SL) (tablets or film). Instruct patient to hold under tongue for 5-10 minutes without swallowing.	Observe patient for 45 to 60 minutes. Symptoms should improve significantly within 30-45 minutes.
Step 3: Escalation to Therapeutic Dose	If withdrawal improves or is partially relieved, administer an additional 8 to 16 mg SL (target total Day-1 dose of 16 to 24 mg).	High Day-1 dosing (>= 16 mg) achieves high mu-receptor occupancy, suppressing cravings and blocking external fentanyl effects for 24-48 hours.
Step 4: Managing Precipitated Withdrawal	If patient acutely worsens after buprenorphine: DO NOT ABANDON THERAPY!	Administer MORE Buprenorphine (8 to 16 mg SL) to rapidly saturate mu receptors and overcome partial occupancy. Adjuncts: Clonidine 0.1-0.2 mg PO, Ketamine 0.3 mg/kg IV slow infusion, and Ondansetron 8 mg IV.

3. Gamma-Hydroxybutyrate (GHB) & Baclofen Withdrawal

Sedative Toxin/Receptor	Withdrawal Presentation & Autonomic Storm	Emergency Pharmacotherapy Protocol
Gamma-Hydroxybutyrate (GHB)/GBL (GABA-B & GHB receptor agonist)	Rapid onset (within 1 to 6 hours of last dose). Rapidly progresses to severe autonomic instability: marked tachycardia, severe hypertension, drenching diaphoresis, gross tremors, paranoia, and bizarre visual, tactile, and auditory hallucinations with agitated delirium.	NOTORIOUSLY REFRACTORY TO STANDARD BENZODIAZEPINES! 1. High-Dose Diazepam: 20 to 40 mg IV every 15-30 minutes (patients often require > 100-200 mg in the first 2-4 hours!). 2. If refractory: Propofol Infusion (direct GABA-A agonist) or Dexmedetomidine (alpha-2 agonist) in an ICU setting. 3. Add Baclofen 10-20 mg PO q8h as an enteral bridge.
Baclofen Withdrawal & Intrathecal Pump Failure (Specific GABA-B receptor agonist)	Occurs when an intrathecal baclofen pump runs dry, kinks, or disconnects in patients with cerebral palsy, multiple sclerosis, or spinal cord injury. - Intense rebound spasticity and rigidity - Hyperthermia (often > 40°C), resembling neuroleptic malignant syndrome - Rhabdomyolysis, seizures, disseminated intravascular coagulation, and multiorgan failure.	IMMEDIATE LIFE-SAVING ACTIONS: 1. Emergency interrogation and refill of pump by Neurosurgery. 2. High-Dose Oral/Enteral Baclofen: 20 to 40 mg PO/NG every 6 hours (high doses required to cross blood-brain barrier). 3. High-dose IV Benzodiazepines. 4. If refractory: Intrathecal Baclofen Bolus (50-100 mcg) via lumbar puncture.

4. Cannabinoid Hyperemesis Syndrome (CHS): Novel Pharmacotherapy

Cannabinoid Hyperemesis Syndrome occurs in chronic, daily cannabis users (> 1 year). Paradoxically, chronic heavy stimulation downregulates peripheral gut CB1 receptors while transiently stimulating central TRPV1 (vanilloid) receptors, producing severe gut dysmotility and hypothermia of the thermoregulatory center:

Clinical Feature	Diagnostic Hallmarks	Effective Emergency Treatment Protocol
Clinical Presentation	1. History of daily or near-daily cannabis use for > 1 year. 2. Recurrent, cyclic, severe paroxysms of intractable nausea and projectile vomiting. 3. Diffuse crampy abdominal pain. 4. Pathognomonic Behavioral Hallmark: Compulsive hot water bathing or showering for hours (hot water activates cutaneous TRPV1 receptors, resetting hypothalamic thermoregulation and providing immediate temporary relief).	Standard antiemetics (Ondansetron, Metoclopramide, Promethazine) ALMOST ALWAYS FAIL! First-Line Targeted Regimens: 1. Topical Capsaicin 0.075% Cream: Apply a thin layer to the abdomen or back (binds and activates cutaneous TRPV1 receptors, mimicking hot water). 2. Haloperidol 2.5 to 5.0 mg IV/IM OR Droperidol 1.25 to 2.5 mg IV (potent D2 and 5-HT3 antagonism in the chemoreceptor trigger zone; achieves rapid cessation of vomiting within 30-45 min).

The Premature Buprenorphine Trap & The Baclofen Pump Hyperthermic Disaster

Two catastrophic pitfalls occur in managing withdrawal syndromes. First, NEVER administer Buprenorphine to an opioid-dependent patient who is not yet in active withdrawal (COWS < 8)! With modern illicit fentanyl storing extensively in adipocytes, patients may test positive on urine drug screens while remaining partially saturated with opioid agonists; administering buprenorphine prematurely triggers violent precipitated withdrawal with uncontrollable vomiting, dehydration, and suicidal agitation. Wait until objective physical signs are evident. Second, in patients with an indwelling intrathecal Baclofen pump, beware sudden catheter dislodgement or pump failure: acute baclofen withdrawal produces an explosive loss of central GABA-B inhibition that produces malignant hyperthermia (> 41°C), massive rhabdomyolysis, and cardiovascular collapse that is frequently misdiagnosed as septic shock or malignant hyperthermia. If an intrathecal pump patient develops severe muscle spasms and fever, immediately administer high-dose enteral Baclofen (20-40 mg PO/NG) and high-dose IV Diazepam while contacting neurosurgery for emergent pump interrogation.

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