What is the recommended dosing and monitoring for patients taking pregabalin (Lyrica) with atomoxetine (Strattera)?

Dosing and Monitoring for Pregabalin with Atomoxetine

When combining pregabalin (Lyrica) with atomoxetine (Strattera), start pregabalin at 50mg three times daily or 75mg twice daily and titrate gradually while monitoring for increased sedation and dizziness, as these medications may have additive central nervous system effects. 1

Pregabalin Dosing

Initial Dosing and Titration

• Start pregabalin at 50mg three times daily or 75mg twice daily 1
• After 3-7 days, increase to 300mg/day if tolerated
• Further titration by 150mg/day every 3-7 days as needed
• Maximum dose: 600mg/day (200mg three times daily or 300mg twice daily) 1
• Duration of adequate trial: 4 weeks

Dose Adjustments for Special Populations

• Renal Impairment: Dose reduction required based on creatinine clearance 1, 2:

  Creatinine Clearance (mL/min)	Pregabalin Daily Dose Range
  ≥60	300-600 mg/day
  30-59	150-300 mg/day
  15-29	75-150 mg/day
  <15	25-75 mg/day

• Elderly Patients: Consider lower starting doses and slower titration 1, 2

Atomoxetine Considerations

While specific information on atomoxetine dosing with pregabalin is limited in the provided evidence, standard atomoxetine dosing should be considered with careful monitoring for potential interactions.

Monitoring Parameters

Initial and Follow-up Monitoring

• First 2-4 weeks: Monitor closely for sedation, dizziness, and cognitive effects 1, 3
• Schedule follow-up within 2-4 weeks to evaluate efficacy and side effects 2
• Assess pain reduction using numerical pain rating scale (0-10) 2

Specific Monitoring

1. CNS Effects:

   • Monitor for excessive sedation, dizziness, feeling drunk, and cognitive impairment 3
   • These are the most common adverse effects and may be additive when combining these medications

2. Renal Function:

   • Baseline and periodic assessment of renal function, as pregabalin is primarily excreted unchanged by the kidneys 4
   • Adjust dose based on creatinine clearance as needed 1

3. Weight Changes:

   • Monitor for increased weight, which is a common side effect of pregabalin 3

4. Blood Pressure and Heart Rate:

   • Regular monitoring recommended, especially with atomoxetine which can affect cardiovascular parameters

5. Mood and Behavior:

   • Watch for changes in mood, behavior, or suicidal ideation 3
   • Report any concerning changes immediately

Potential Drug Interactions and Adverse Effects

Common Adverse Effects

• Pregabalin: Dizziness (most common), somnolence, feeling drunk, fatigue, weight gain 3
• Combined therapy: May have additive CNS depression effects

Timing of Adverse Effects

• Most adverse effects appear within the first few days of treatment 3, 5
• Tolerance to dizziness and somnolence typically develops within a few weeks 5

Management of Adverse Effects

• For dizziness and somnolence: Consider temporary dose reduction or slower titration 1
• For peripheral edema: Monitor closely as this may be more common with higher doses of pregabalin 6

Clinical Pearls

1. Onset of Action:

   • Pregabalin may provide analgesia more quickly than other medications used for neuropathic pain 1
   • Initial efficacy may be observed within the first week of treatment 7

2. Pharmacokinetic Advantages:

   • Pregabalin has linear pharmacokinetics with high bioavailability 4
   • Not subject to hepatic metabolism and does not induce or inhibit liver enzymes 4
   • Minimal drug-drug interactions via hepatic mechanisms 4

3. Discontinuation:

   • Avoid abrupt discontinuation of pregabalin 2
   • Taper gradually to prevent withdrawal symptoms 5

4. Common Pitfalls to Avoid:

   • Inadequate dosing is a common reason for treatment failure 2
   • Failure to adjust doses based on renal function 1, 4
   • Overlooking additive sedative effects when combining with other CNS depressants

By following these dosing and monitoring recommendations, clinicians can optimize the safety and efficacy of combined pregabalin and atomoxetine therapy for patients requiring both medications.