What is the best treatment approach for a patient with gastroparesis and fibromyalgia experiencing severe vomiting, diarrhea, dehydration, dizziness, lightheadedness, and headache, who frequently presents to the emergency room (ER) for intravenous (IV) fluids and hydromorphone (Dilaudid)?

Management of Gastroparesis with Suspected Opioid-Seeking Behavior

This patient requires immediate IV fluid resuscitation for severe dehydration, but hydromorphone should be avoided and replaced with non-opioid alternatives, as opioids worsen gastroparesis and the presentation suggests potential medication-seeking behavior. 1, 2

Immediate Emergency Department Management

Assess and Treat Dehydration

• Check for at least four of these seven signs indicating moderate-to-severe volume depletion: confusion, non-fluent speech, extremity weakness, dry mucous membranes, dry tongue, furrowed tongue, and sunken eyes 3
• Administer isotonic IV fluids immediately for rehydration, as this patient cannot keep oral fluids down 3
• Monitor electrolytes closely, as severe vomiting and diarrhea can cause dangerous imbalances 3

Address Pain Without Opioids

• Use IV ketorolac as first-line non-narcotic analgesic for abdominal pain associated with gastroparesis, explicitly avoiding hydromorphone 3
• Opioids including hydromorphone directly worsen gastroparesis by inducing pyloric dysfunction and gastric stasis, making them contraindicated in this condition 3, 1
• The frequent ER presentations specifically requesting hydromorphone is a red flag for potential opioid use disorder, which requires separate addiction medicine evaluation 1

Control Vomiting Aggressively

• Administer IV ondansetron (5-HT3 antagonist) for immediate antiemetic effect 1
• Add IV promethazine or prochlorperazine (antidopaminergic agents) for additional nausea control 1
• Consider IV droperidol or haloperidol for refractory vomiting in the ED setting 3
• Induce sedation with IV benzodiazepines in a quiet, darker room, as sedation itself is therapeutic for severe nausea and vomiting 3

Manage Concurrent Diarrhea

• Start oral loperamide 4 mg initially, then 2 mg every 2 hours (maximum 16 mg/day) 4
• If diarrhea persists beyond 24 hours despite loperamide, add oral fluoroquinolone for 7 days to cover possible bacterial overgrowth 3
• Send stool studies for C. difficile, bacterial pathogens, and fecal leukocytes if fever is present 4

Inpatient Management Strategy

Optimize Gastroparesis Treatment

• Start metoclopramide 10 mg three times daily before meals (the only FDA-approved medication for gastroparesis), but limit use to 12 weeks maximum due to tardive dyskinesia risk 1, 2
• Implement strict dietary modifications: 5-6 small meals daily, low-fat (<30% of calories), low-fiber, small particle size foods 1, 5
• Replace solid foods with liquids such as soups and nutrient-dense liquid supplements 1, 5
• Withdraw all medications that worsen gastroparesis, particularly any opioids the patient may be taking 1

Address Fibromyalgia Without Opioids

• Fibromyalgia pain should be managed with non-opioid approaches including tricyclic antidepressants, SNRIs (duloxetine), or gabapentinoids 1
• Note that tricyclic antidepressants have anticholinergic effects that may worsen gastroparesis, so SNRIs are preferred 1

Nutritional Support

• If oral intake remains below 50-60% of energy requirements for more than 10 days despite dietary modifications, place a jejunostomy tube (not gastrostomy, which would not bypass the delayed gastric emptying) 5
• Target 25-30 kcal/kg/day and protein intake of 1.2-1.5 g/kg/day 5
• Monitor weight weekly and assess for micronutrient deficiencies (vitamin B12, vitamin D, iron, calcium) 5

Refractory Gastroparesis Management

If Symptoms Persist After 4 Weeks

• Add erythromycin (oral or IV) as a second prokinetic agent, though be aware of tachyphylaxis with prolonged use 1
• Consider domperidone if available (not FDA-approved in US but available in Canada/Mexico) 1
• Intensify antiemetic therapy with scheduled rather than as-needed dosing 1

Tertiary Care Interventions

• Do NOT use intrapyloric botulinum toxin injection, as placebo-controlled studies show no benefit 1
• Refer to a tertiary center for gastric electrical stimulation (GES) if medically refractory 1, 6
• Consider gastric per-oral endoscopic myotomy (G-POEM) only at expert centers for truly refractory cases 3, 1

Critical Pitfalls to Avoid

• Never prescribe hydromorphone or other opioids for gastroparesis-related pain, as they are iatrogenic causes of worsening gastroparesis 3, 1
• Do not place a gastrostomy (PEG) tube in gastroparesis patients, as it delivers nutrition into the dysfunctional stomach and will not help 5
• Do not continue metoclopramide beyond 12 weeks without careful reassessment of risks versus benefits due to tardive dyskinesia risk 1, 2
• Do not delay jejunal tube feeding beyond 10 days of inadequate oral intake, as malnutrition significantly worsens outcomes 5

Addressing Potential Substance Use Disorder

• The pattern of frequent ER visits specifically requesting hydromorphone, combined with a chronic pain condition (fibromyalgia), raises concern for opioid use disorder 7
• Consult addiction medicine or psychiatry for formal evaluation and potential medication-assisted treatment 1
• Establish a care plan with the patient's primary care physician to coordinate outpatient management and prevent ER "shopping" 1
• Document clearly in the medical record that opioids are contraindicated for this patient's gastroparesis and worsen the underlying condition 3, 1