What are the considerations before taking Reglan (metoclopramide)?

Considerations Before Taking Reglan (Metoclopramide)

Before starting Reglan, you must be screened for absolute contraindications including gastrointestinal bleeding/obstruction/perforation, pheochromocytoma, seizure disorders, and concurrent use of medications causing movement disorders, as these represent dangerous or life-threatening situations where metoclopramide is contraindicated. 1

Absolute Contraindications

Do not take metoclopramide if you have: 1, 2

• Gastrointestinal bleeding, blockage, or perforation - the drug could worsen these conditions
• Pheochromocytoma (adrenal gland tumor) - can trigger hypertensive crisis
• Known allergy to metoclopramide or any ingredient
• Current use of medications causing movement disorders (antipsychotics, other dopamine antagonists)
• Seizure disorder - metoclopramide may lower seizure threshold 1

High-Risk Patient Populations Requiring Extreme Caution

Neurological Risk Factors

Elderly women with diabetes represent the highest risk group for tardive dyskinesia and should only receive metoclopramide when benefits clearly outweigh risks. 1, 3

Risk factors for irreversible movement disorders include: 1, 3

• Age over 65 years, especially women
• Diabetes mellitus - increases risk substantially
• Duration of therapy exceeding 12 weeks - risk increases with cumulative exposure
• Higher doses (>30-40 mg daily)

Renal Impairment

Patients with creatinine clearance below 40 mL/min must start at half the standard dose due to primarily renal excretion of metoclopramide. 1, 4 Failure to adjust dosing in renal failure significantly increases the risk of parkinsonism and other neurological complications. 4

Depression and Mental Health

Screen for depression, suicidal ideation, or history of suicide attempts before prescribing - metoclopramide can cause or worsen depression and has been associated with completed suicide. 1 This is particularly important in patients under 24 years old.

Cardiovascular Conditions

Evaluate for: 1

• Uncontrolled hypertension - use with caution
• Heart failure - metoclopramide may cause fluid retention
• Conduction abnormalities - can prolong QT interval with repeated doses 5

Medication Interactions Requiring Review

Review all current medications before starting metoclopramide, as dangerous interactions can occur: 1, 2

• MAO inhibitors - contraindicated combination
• Tricyclic antidepressants - may reduce metoclopramide effectiveness 2
• Anticholinergic medications - antagonize metoclopramide's effects
• Sedating medications (benzodiazepines, opioids, sleep aids) - additive sedation 1
• Insulin or sulfonylureas - metoclopramide affects gastric emptying and may require dose adjustment 1
• Oral contraceptives - absorption may be delayed, requiring backup contraception 6
• Digoxin, cyclosporine - absorption may be altered

Special Populations

Pregnancy and Breastfeeding

• Pregnancy: Unknown if harmful to fetus; use only if benefits justify potential risks 1
• Breastfeeding: Metoclopramide passes into breast milk and may harm the infant - discuss alternative feeding methods 1

Parkinson's Disease

Patients with pre-existing Parkinson's disease will experience worsening of symptoms due to metoclopramide's dopamine-blocking effects. 1 Consider alternative therapies.

Hepatic Impairment

While metoclopramide undergoes minimal hepatic metabolism, use caution in advanced liver disease, particularly if renal function is also compromised. 1

Critical Warnings About Duration of Use

Metoclopramide should not be taken for more than 12 weeks - the risk of tardive dyskinesia increases substantially with longer duration, and there is no established benefit for extended therapy. 1 The actual risk of tardive dyskinesia is approximately 0.1% per 1000 patient-years, far lower than previously estimated, but the condition is potentially irreversible. 3

Baseline Assessments Needed

Before starting therapy, document: 1

• Baseline movement examination - to identify any pre-existing abnormal movements
• Mental health screening - depression, suicidal ideation
• Renal function (creatinine clearance) - to guide dosing
• Complete medication list - to identify interactions
• Cardiovascular history - particularly arrhythmias or heart failure

Common Side Effects to Anticipate

Patients should be counseled about expected side effects: 1, 7

• Drowsiness and fatigue (most common) - avoid driving until effects are known
• Restlessness and akathisia - inner sense of restlessness
• Diarrhea or constipation
• Headache

Red Flag Symptoms Requiring Immediate Discontinuation

Stop metoclopramide immediately and contact physician if: 1

• Uncontrolled facial movements (lip smacking, tongue protrusion, facial grimacing)
• Muscle spasms of face, neck, or body (dystonic reactions)
• Severe muscle rigidity with high fever (neuroleptic malignant syndrome)
• Worsening depression or suicidal thoughts
• Tremor or shuffling gait (parkinsonism)