In a patient with recent back surgery, lumbar pain, abdominal pain with bowel incontinence, IBS, coronary artery disease, and current medications methocarbamol, nortriptyline 25 mg daily, gabapentin 400 mg three times daily, atorvastatin, and hydroxyzine PRN, should I continue the Orphenadrine citrate extended‑release prescribed in the emergency department?

Discontinue Orphenadrine Immediately

You should stop the orphenadrine citrate ER prescribed in the emergency department due to significant safety concerns in this patient with coronary artery disease and multiple contraindications. 1, 2

Critical Safety Issues with Orphenadrine

Cardiac Contraindications

• Orphenadrine is specifically contraindicated or requires extreme caution in patients with coronary artery disease, cardiac arrhythmias, cardiac decompensation, coronary insufficiency, and tachycardia—all of which apply to your patient with documented coronary artery disease. 2
• The FDA label explicitly warns against use in patients with cardiac conditions due to anticholinergic cardiovascular instability, including potential for arrhythmias and hemodynamic compromise. 2

Redundancy with Current Regimen

• This patient is already taking methocarbamol four times daily for muscle relaxation, making orphenadrine completely redundant—both are centrally-acting skeletal muscle relaxants with similar mechanisms and no evidence that combining them provides additional benefit. 1
• The Society for Perioperative Assessment and Quality Improvement (SPAQI) consensus recommends holding centrally-acting muscle relaxants like orphenadrine and methocarbamol on the day of operation due to CNS depression and lack of direct skeletal muscle action. 1

Anticholinergic Burden

• Orphenadrine has significant anticholinergic properties that can worsen constipation, urinary retention, confusion, and anxiety—particularly problematic in a patient with IBS and bowel incontinence. 2
• The anticholinergic effects include dry mouth, constipation, urinary retention, confusion, anxiety, and tremors, which can exacerbate existing gastrointestinal symptoms. 2

What to Do Instead

Optimize Current Pain Management

• Continue methocarbamol at the current dose (four times daily) as the sole muscle relaxant, since it is already providing whatever benefit a centrally-acting agent can offer. 1
• Maintain nortriptyline 25 mg daily for neuropathic pain—this tricyclic antidepressant is evidence-based for both neuropathic pain and IBS symptom management. 3, 4, 5
• Continue gabapentin 400 mg three times daily for lumbar radicular pain, as this is appropriate dosing for neuropathic pain in the post-surgical spine patient. 1

Address the Bowel Incontinence Urgently

• The combination of abdominal pain with bowel incontinence in a patient on multiple CNS-active medications (methocarbamol, nortriptyline, gabapentin, hydroxyzine) raises concern for overflow incontinence from severe constipation or fecal impaction. 1
• Perform a digital rectal exam immediately to rule out fecal impaction, especially since diarrhea accompanying constipation suggests overflow around impaction. 1
• Obtain abdominal imaging (plain x-ray or CT) to rule out bowel obstruction or ileus, particularly given recent back surgery and current use of multiple constipating medications. 1

Constipation Management Algorithm

• If impaction is present: perform manual disimpaction following pre-medication with analgesic ± anxiolytic, then administer glycerine suppository ± mineral oil retention enema. 1
• Add bisacodyl 10–15 mg daily, titrating up to three times daily with a goal of one non-forced bowel movement every 1–2 days. 1
• Consider adding polyethylene glycol (1 capful in 8 oz water twice daily) or lactulose 30–60 mL twice to four times daily if bisacodyl alone is insufficient. 1

IBS-Specific Considerations

• The nortriptyline 25 mg daily is appropriate for IBS management—tricyclic antidepressants at low doses (10–30 mg) are evidence-based second-line treatment for IBS when first-line therapies fail. 4, 5
• Consider titrating nortriptyline up to 30 mg if IBS symptoms persist, as the ATLANTIS trial demonstrated significant benefit with titrated low-dose amitriptyline (10–30 mg) for refractory IBS. 4

Common Pitfalls to Avoid

• Do not continue orphenadrine simply because it was prescribed in the emergency department—ED prescriptions for muscle relaxants are often inappropriate for patients with cardiac disease and polypharmacy. 1, 2
• Do not add another muscle relaxant on top of methocarbamol—there is no evidence for synergistic benefit and substantial risk of additive CNS depression and anticholinergic toxicity. 1, 2
• Do not assume bowel incontinence is purely IBS-related without ruling out mechanical causes (impaction, obstruction) or medication-induced ileus, especially in a post-surgical patient on multiple constipating agents. 1
• Do not discontinue nortriptyline in an attempt to reduce anticholinergic burden—it is serving dual purposes (neuropathic pain and IBS management) and is better tolerated than orphenadrine. 3, 4, 5