Cannabinoid Hyperemesis Syndrome (CHS) - Treatment Plan (USA Guidelines 2024-2025)

Diagnosis Confirmation

• Episodic nausea, vomiting, and colicky abdominal pain
• Heavy, chronic cannabis use (typically daily or near-daily, for months to years)
• Recurrent stereotyped episodes (same pattern as prior episodes - as in your patient)
• Compulsive hot bathing behavior (pathognomonic if present, but not required)
• Resolution of symptoms with cannabis cessation
• No other explanation after appropriate workup on first presentation

Note on headache: While headache is not a classic CHS feature, it is likely a consequence of dehydration, electrolyte disturbance, or associated cannabis withdrawal. Rule out CNS cause if red flags present (thunderclap, meningismus, focal neuro deficits).

Rule Out Before Diagnosing CHS

• Acute abdomen (appendicitis, pancreatitis, bowel obstruction) - surgical consult if tenderness is focal or peritoneal signs present
• Cyclic vomiting syndrome (CVS) - same management, but no cannabis link
• Small bowel obstruction, gastroparesis
• Intracranial pathology (if headache is severe or atypical)
• Pregnancy (urine hCG in women of childbearing age)
• Basic labs: BMP (electrolytes, BUN/Cr for AKI and dehydration), LFTs, lipase, CBC

Phase-Based Treatment Plan

ACUTE/HYPEREMETIC PHASE - Emergency Department Management

1. IV Fluid Resuscitation

• Normal saline (NS) bolus 1-2 L IV for dehydration/volume repletion
• Correct electrolyte abnormalities (hypokalemia, hyponatremia are common)
• Maintenance fluids until tolerating oral intake

2. Antiemetics - STEP-WISE APPROACH

• Ondansetron (Zofran) 4 mg IV q6h - used as baseline, but CHS is often resistant to 5-HT3 antagonists alone
• Metoclopramide 10 mg IV q6h (dopamine antagonist, also prokinetic)

• Haloperidol 0.5-2 mg IV q6h PRN - D2 antagonist; off-label but now guideline-supported. A 2024 RCT (Ruberto et al.) showed haloperidol 0.05-0.1 mg/kg was MORE effective than ondansetron in reducing nausea/vomiting (p=0.01) and led to shorter ED stays (p=0.03). Monitor QTc. Pre-treat with diphenhydramine 25-50 mg IV to prevent dystonia.
• Droperidol 1.25-2.5 mg IV - Alternative to haloperidol; similar D2 mechanism, also GRACE-4 recommended. Black box warning for QT prolongation - obtain ECG first.
• Lorazepam 1-2 mg IV/IM - Useful if haloperidol/droperidol unavailable or contraindicated; provides sedation and antiemetic effect.

GRACE-4 (2024) recommendation: "In adult ED patients presenting with CHS, we suggest the use of haloperidol or droperidol (in addition to usual care/serotonin antagonists) to help with symptom management."

3. Topical Capsaicin - STRONGLY RECOMMENDED

• Capsaicin cream 0.025-0.1% applied to the abdomen and/or back
• Mechanism: TRPV1 agonist - depletes substance P, counteracting the hyperemetic pathway; also mimics the hot shower relief phenomenon
• Apply q6-8h during acute episode
• GRACE-4 (2024): "We suggest offering topical capsaicin (in addition to usual care) to help with symptom management."
• Per Rosen's EM: "ED treatment of CHS includes the use of capsaicin cream as well as haloperidol or lorazepam."

4. Pain Management

• Avoid opioids - Parenteral narcotics are contraindicated in CHS; they exacerbate hyperemesis and carry addiction risk
• Ketorolac 30 mg IV or ibuprofen 600 mg PO for abdominal pain (once rehydrated and no AKI)
• If pain is severe and refractory, consider low-dose ketamine (0.1-0.3 mg/kg IV) as an adjunct

5. Hot Shower/Bath

• Allow the patient controlled access to a warm shower if possible - it is the only thing patients often find genuinely relieving (TRPV1-mediated)
• Do not restrict this; acknowledge it as part of the syndrome

INPATIENT CRITERIA (Admit If:)

• Persistent intractable vomiting despite ED treatment
• Significant dehydration, AKI (Cr elevation), or electrolyte abnormality not correcting
• Unable to tolerate PO
• BMI severely low or nutritional compromise
• First episode requiring full workup

• Continue IV antiemetics on schedule (not just PRN)
• TPN or NG feeds only if prolonged inability to eat (rare)
• Psychiatry/addiction medicine consult for cannabis use disorder counseling
• Social work referral

RECOVERY PHASE - The Only Definitive Treatment

• Educate the patient clearly: cannabis USE perpetuates CHS - this is paradoxical to what patients believe (many self-medicate with more cannabis)
• Symptoms typically resolve within 24-48 hours of complete cessation; full recovery may take 1-3 months
• Relapse with any cannabis use restarts the cycle

OUTPATIENT / LONG-TERM MANAGEMENT

1. Addiction Medicine / Behavioral Counseling

• Refer to substance use disorder specialist
• Cognitive behavioral therapy (CBT) for cannabis use disorder
• Motivational interviewing
• The 2024 AGA Clinical Practice Update specifically recommends combining evidence-based psychosocial interventions with pharmacological treatments for long-term CHS management

2. Pharmacotherapy for Cannabis Use Disorder (if needed)

• No FDA-approved pharmacotherapy specifically for cannabis use disorder (CUD) as of 2025
• Off-label options used in practice: N-acetylcysteine, gabapentin, nabilone - limited evidence
• Treat any comorbid anxiety/depression (often co-occurring with CUD)

3. Cyclic Vomiting Syndrome (CVS) Prophylaxis

• Amitriptyline 10-75 mg PO QHS - first-line prophylaxis (as in CVS)
• Topiramate 25-100 mg/day - alternative prophylaxis
• Coenzyme Q10 + L-carnitine - adjunctive for mitochondrial support
• Prophylaxis is second-line only - abstinence remains primary

4. Discharge Instructions

• Written education on CHS diagnosis and the cannabis-vomiting link
• Prescription: Ondansetron 4 mg PO q8h x 3 days OR promethazine 12.5-25 mg q6h PRN (bridge until follow-up)
• Capsaicin cream 0.025% (OTC) - instruct patient to apply to abdomen with any future prodromal symptoms
• Follow-up with PCP or GI within 1-2 weeks
• Return precautions: inability to keep fluids down >24h, AMS, severe abdominal pain, oliguria

Monitoring & Safety Checklist

Key References

• SAEM GRACE-4 Practice Guideline (2024) - Borgundvaag et al., Academic Emergency Medicine [PMID 38747203] - Haloperidol/droperidol + capsaicin for ED management
• Rosen's Emergency Medicine (10th ed.) - "ED treatment of CHS includes capsaicin cream and haloperidol or lorazepam"
• Sleisenger and Fordtran's GI & Liver Disease - CHS pathophysiology and abortive treatments
• AGA Clinical Practice Update 2024 - Psychosocial + pharmacologic combination for long-term management
• PMC Comprehensive Review 2024 (PMC11597608) - Full treatment table including haloperidol dosing, capsaicin, aprepitant, scopolamine patch

Quick Summary

CHS - OTC Home Treatment Plan (USA)

Important disclaimer: These are for mild-to-moderate episodes in a patient with a known CHS diagnosis. If the patient cannot keep any fluids down for >12 hours, shows signs of severe dehydration (no urination, dizziness on standing, confusion), or has severe abdominal pain - they need the ED, not home treatment.

#1 - Capsaicin Cream (Most CHS-Specific OTC Option)

#2 - Oral Rehydration

• Pedialyte or Liquid I.V. electrolyte sachets - better than plain water
• Gatorade/Powerade - acceptable alternative
• Sip slowly in small amounts (2-3 oz every 10-15 min) rather than large gulps
• Ginger ale (flat) or ginger tea - ginger has mild antiemetic properties; helps settle the stomach between sips
• Avoid: citrus juices, milk, coffee, alcohol - these worsen nausea

#3 - OTC Antiemetics (Limited Efficacy in CHS, but Worth Trying)

#4 - OTC Pain Relief for Abdominal Cramping/Headache

#5 - Hot Shower/Bath (Non-Drug but Highly Effective)

• Warm to hot shower or bath is the hallmark compulsive behavior in CHS
• It genuinely and temporarily relieves nausea/vomiting via TRPV1 stimulation (same mechanism as capsaicin)
• Use it during acute peaks - it is not harmful
• Limit to avoid dehydration worsening (prolonged soaking = more fluid loss through sweat)

#6 - Rest, Diet, Environment

• Nothing by mouth for 30-60 minutes if actively vomiting, then restart sips
• BRAT diet (Bananas, Rice, Applesauce, Toast) once tolerating fluids
• Cool, dark, quiet room - stimuli worsen nausea
• Elevate head of bed 30 degrees
• Stop all cannabis immediately - this is not optional and is the only thing that will break the cycle

When to Stop Home Treatment and Go to the ED

• No urination for >8 hours (severe dehydration)
• Cannot keep even small sips of fluid down for >12 hours
• Vomiting blood or "coffee grounds" material
• Severe/worsening abdominal pain (not just cramping)
• Confusion, extreme weakness, or fainting
• Headache is the "worst of your life" or with neck stiffness/fever
• Home treatment not working after 6-8 hours of trying

One-Page Summary

STOP cannabis completely.

Step 1 → Apply capsaicin 0.025% cream to abdomen + back (every 6-8 hrs)
Step 2 → Sip Pedialyte slowly (2-3 oz every 15 min)
Step 3 → Take Dramamine 50 mg or Pepto-Bismol for nausea
Step 4 → Hot shower for symptom peaks
Step 5 → Ibuprofen 400 mg (if drinking fluids) OR Tylenol for pain/headache
Step 6 → Rest in dark, cool room; BRAT diet when able

Go to ER if: no pee 8+ hrs, can't hold fluids 12+ hrs, blood in vomit,
            confusion, or severe pain that is worsening.

Revised Clinical Assessment

Is This Really CHS?

1. When did the "similar episodes in past" occur? - If they happened before May, cannabis is NOT the cause. If they started after May when he began cannabis, that strengthens CHS.
2. Was he using cannabis before May at any point? - He may have a longer use history than reported. Patients often underreport.
3. What does "low amount" mean? - Even small amounts of high-THC products (concentrates, dabs, edibles) can trigger CHS. Modern cannabis THC content is 20-30%, much higher than decades ago.

If Episodes Preceded Cannabis Use - Think These First

Revised Diagnostic Approach

Do a Proper Workup - Do Not Anchor on CHS

• BMP, CBC, LFTs, lipase, TSH
• H. pylori stool antigen
• Urine hCG (if female)
• Urinary THC-COOH level (if available) - levels >100 ng/mL confirm significant chronic exposure

• Upper abdominal ultrasound (gallstones, hepatobiliary pathology)
• Consider CT abdomen/pelvis if pain is significant or exam is abnormal

• Upper endoscopy (EGD) if recurrent - rule out peptic ulcer, gastritis, eosinophilic esophagitis
• Gastric emptying scintigraphy if gastroparesis suspected

• The headache component needs attention - could be migraine, which also causes cyclic vomiting

What This Means for Treatment Right Now

Do NOT tell the patient "stop cannabis and you'll be fine" yet

• The vomiting may not resolve with cannabis cessation
• Premature labeling as CHS can cause you to miss a structural or functional GI diagnosis
• The patient may also not accept the diagnosis, reducing trust

What to Do Instead

1. Treat symptoms as outlined in the OTC plan (capsaicin, hydration, Dramamine, hot shower)
2. Advise cannabis reduction/cessation as a diagnostic trial - frame it as "we want to see if stopping cannabis for 2-4 weeks helps identify the cause" rather than "you have CHS"
3. Document the episode pattern carefully - date of onset, frequency, duration, triggers, relieving factors
4. Schedule outpatient follow-up with PCP or GI within 1-2 weeks for the workup above
5. If episodes continue after cannabis cessation - pursue full CVS/functional GI workup

Bottom Line

Updated Clinical Picture - CHS Confirmed (High Confidence)

What This Changes Clinically

1. Diagnosis is Confirmed - No Extensive Workup Needed

2. The Core Message to This Patient

• Cannabis ON → episodes come back
• Cannabis OFF → episodes stop

"You stopped before and your vomiting went away. You restarted in May and it came back. Your body is telling you exactly what the cause is. Every time you use cannabis, even a small amount daily, you are restarting this cycle."

Revised Treatment Plan - Known CHS with Relapse

Immediate / Acute (Home OTC - same as before)

• Capsaicin 0.025% cream to abdomen every 6-8 hrs
• Pedialyte/oral rehydration - slow sips
• Dramamine 50 mg or Pepto-Bismol for nausea
• Ibuprofen/Tylenol for pain and headache
• Hot shower for acute peaks
• Go to ED if cannot hold fluids >12 hrs or signs of severe dehydration

The Only Long-Term Fix - Complete Cannabis Cessation

Cessation Support - OTC / Low-Barrier Options

• SAMHSA National Helpline: 1-800-662-4357 (free, confidential, 24/7)
• Online: findtreatment.gov - free cannabis use disorder programs
• Marijuana Anonymous: marijuana-anonymous.org - 12-step, free

What to Prescribe / Refer at Next Visit

Key Summary for This Patient Specifically

CONFIRMED CHS - Relapse triggered by restarting cannabis in May.

Proven history:
  Cannabis stopped before → vomiting stopped
  Cannabis restarted May → vomiting returned
  This IS the diagnosis.

Home treatment (current episode):
  → Capsaicin 0.025% cream on abdomen q6-8h (most important)
  → Pedialyte sips every 15 min
  → Dramamine 50 mg for nausea
  → Hot shower for acute peaks
  → Tylenol/Ibuprofen for headache

Definitive treatment:
  → STOP cannabis completely - not reduce, STOP
  → Expect symptom resolution in 24-72 hrs
  → Full recovery in 1-4 weeks

Follow up in 1-2 weeks for:
  → Addiction counseling referral
  → Prophylactic therapy if episodes recur despite cessation

What is Pedialyte?

What's In It (Standard Formula)

Why Not Just Plain Water?

• They lose sodium and potassium, not just water
• Drinking plain water dilutes remaining electrolytes further
• Can worsen hyponatremia
• Does not get absorbed as efficiently

Where to Buy in USA

• Walgreens, CVS, Walmart, Target, Amazon
• Comes as: ready-to-drink bottles, powder packets, freezer pops, and advanced sport formulas
• Cost: ~$7-10 for a 1-liter bottle

Alternatives if Pedialyte is Not Available

How to Use It in CHS

• Do not gulp - small sips of 2-3 oz (60-90 mL) every 10-15 minutes
• If the patient vomits after a sip, wait 10 minutes then try again
• Once tolerating sips for 30 minutes without vomiting, increase volume gradually
• Goal: at least 500 mL-1 liter over the first 2-4 hours

Pedialyte Flavors (USA - Available at CVS, Walgreens, Walmart)

Classic Ready-to-Drink

Pedialyte Sport (Higher Sodium)

• Fruit Punch
• Lemon Lime
• Berry Frost
• Orange Burst

Pedialyte Freezer Pops

• Grape, Cherry, Orange, Blue Raspberry
• Good option for CHS patients who can't tolerate drinking - they suck slowly on the pop which delivers small amounts at a time

Best Flavor Choice for a CHS/Vomiting Patient

Grape vs Berry for a Vomiting Patient

Recommendation

• The scent is milder and less sweet than berry
• Most people associate grape with medicine/sick-day drinks (familiar, not off-putting)
• Less likely to smell overwhelming when nauseous
• Berry can sometimes smell too sweet when the stomach is upset

Emetrol - Quick Overview

What Is It?

• The hyperosmolar sugar solution directly relaxes smooth muscle of the stomach wall
• Reduces gastric hypermotility and spasm that drives nausea/retching
• Phosphoric acid has a mild local soothing effect on the GI tract

How to Use

Flavors Available

• Cherry (most popular)
• Lemon Mint
• Unflavored (original clear)

Is It Useful for CHS?

How It Fits Into the CHS Home Plan

Nausea starts →
  1. Take Emetrol 15-30 mL immediately
  2. Apply capsaicin cream to abdomen
  3. Get in hot shower
  4. After 15 min, start sipping Pedialyte grape
  5. If not improving in 1-2 hrs → Dramamine 50 mg