What is the treatment for extrapyramidal side effects caused by metoclopramide (antiemetic medication)?

Treatment for Extrapyramidal Side Effects of Metoclopramide

For acute extrapyramidal side effects caused by metoclopramide, the first-line treatment is administration of anticholinergic medications such as diphenhydramine 50 mg intramuscularly or benztropine 1-2 mg intramuscularly, which typically resolve symptoms rapidly. 1

Types of Extrapyramidal Side Effects (EPS) from Metoclopramide

Metoclopramide can cause several types of extrapyramidal reactions:

1. Acute Dystonic Reactions

   • Occur in approximately 1 in 500 patients
   • Usually appear within first 24-48 hours of treatment
   • More common in patients under 30 years and pediatric patients
   • Present as involuntary movements, facial grimacing, torticollis, oculogyric crisis, tongue protrusion, trismus, or tetanus-like reactions
   • Rarely may present as stridor and dyspnea due to laryngospasm

2. Akathisia

   • Characterized by subjective feelings of inner restlessness
   • Objective signs include rocking while standing/sitting, lifting feet as if marching

3. Parkinsonian-like Symptoms

   • Include bradykinesia, tremor, cogwheel rigidity, mask-like facies
   • More common within first 6 months of treatment
   • Generally subside within 2-3 months after discontinuation

4. Tardive Dyskinesia

   • Risk increases with duration of treatment and cumulative dose
   • Potentially irreversible

Treatment Algorithm

For Acute Dystonic Reactions:

1. First-line treatment:

   • Diphenhydramine (Benadryl) 50 mg intramuscularly 1
   • OR Benztropine mesylate (Cogentin) 1-2 mg intramuscularly 1
   • Symptoms typically subside quickly after administration

2. Additional measures:

   • Discontinue metoclopramide if possible 1
   • If symptoms are severe, consider IV administration of anticholinergics for faster onset

For Akathisia:

1. First-line treatment:

   • Propranolol 10-30 mg two to three times daily 2
   • Use cautiously in patients with asthma, diabetes, or cardiovascular disease

2. Alternative options:

   • Lorazepam 0.5-2 mg as needed (note: regular use can lead to tolerance) 2
   • Consider switching to an alternative antiemetic with lower EPS risk

For Parkinsonian-like Symptoms:

1. Primary intervention:

   • Discontinue metoclopramide if possible 1
   • Symptoms generally subside within 2-3 months after discontinuation

2. Symptomatic treatment:

   • Anticholinergic medications (benztropine 1-2 mg daily) 2, 3
   • Maximum benztropine dose: 6 mg daily 2

For Tardive Dyskinesia:

1. Critical first step:

   • Immediate discontinuation of metoclopramide 1
   • There is no known effective treatment for established cases

2. Potential options for symptom management:

   • Consider VMAT2 inhibitors (valbenazine or deutetrabenazine) 2
   • In some patients, TD may partially or completely remit within several weeks to months after metoclopramide withdrawal 1

Special Considerations

• High-risk populations for developing EPS include:

  • Patients under 30 years of age 1, 4
  • Elderly patients 2
  • Women 4
  • Patients with AIDS 4
  • Patients with renal disease 4
  • Oncology patients 4

• Prevention strategies:

  • Use metoclopramide for the shortest duration possible
  • Avoid treatment longer than 12 weeks to reduce TD risk 1
  • Consider alternative antiemetics in high-risk patients

• Monitoring:

  • For patients requiring continued metoclopramide, monitor regularly for emergence of EPS
  • Use standardized scales like AIMS (Abnormal Involuntary Movement Scale) every 3-6 months 2

• Important caveat:

  • Metoclopramide itself may suppress or partially suppress the signs of TD, potentially masking the underlying disease process 1
  • Therefore, metoclopramide should not be used for symptomatic control of TD

Medication Interactions

• Be aware of potential serotonin syndrome with serious extrapyramidal reactions when metoclopramide is coadministered with SSRIs or SNRIs 5
• Treatment of serotonin syndrome with EPS may require diazepam 5

Remember that prompt recognition and treatment of EPS is essential to prevent progression to more serious or potentially irreversible movement disorders.