What are the potential side effects of using Lyrica (pregabalin) and hydroxychloroquine together?

Potential Side Effects of Using Lyrica (Pregabalin) and Hydroxychloroquine Together

When combining Lyrica (pregabalin) and hydroxychloroquine, the primary concern is additive central nervous system effects (dizziness, confusion, drowsiness) and the individual side effect profiles of each medication, though no specific dangerous drug-drug interaction between these two agents has been documented in the medical literature.

Individual Side Effect Profiles

Hydroxychloroquine Side Effects

Gastrointestinal Effects:

• Nausea, vomiting, and diarrhea are the most common side effects, particularly at treatment initiation 1
• These symptoms are generally infrequent at standard doses 2

Cardiac Toxicity:

• QT interval prolongation and risk of ventricular arrhythmias, particularly when combined with other QT-prolonging medications 2
• Cardiac disease including heart failure and myocardial infarction is a contraindication 2
• Long-term use can cause cardiomyopathy and conduction abnormalities 3, 1
• ECG monitoring is recommended, especially with concurrent QT-prolonging drugs 2

Neuropsychiatric Effects:

• Confusion, disorientation, and hallucinations may occur within 24-48 hours of drug initiation 1
• Psychosis, depression, suicidal ideation, mania/hypomania, anxiety, sleep disturbances, and cognitive impairments have been reported 4
• Headache and dizziness are common but usually don't require discontinuation 2

Ocular Toxicity:

• Retinopathy is the major dose-limiting toxicity with long-term use, particularly at doses exceeding 250 mg/day 3
• Risk increases with age, dose, and duration of use 1
• Baseline ocular examination within the first year and annual examinations for high-risk patients are recommended 2
• Blurred vision may occur early in treatment 2, 5

Dermatologic Effects:

• Drug eruptions or rashes are common 1, 6
• Cutaneous hyperpigmentation, pruritus, lichenoid skin eruptions, and bleaching of hair 3, 6
• Stevens-Johnson syndrome and toxic epidermal necrolysis are rare but serious 1, 6
• Most reactions resolve with discontinuation 1

Neuromuscular Toxicity:

• Prolonged therapy can cause toxic myopathy, peripheral neuropathy, and rarely cardiomyopathy 3, 5
• These reactions improve if the drug is promptly withdrawn 3

Other Effects:

• Ototoxicity with irreversible hearing loss, particularly at doses exceeding 250 mg/day 3, 7
• ECG abnormalities including widening of QRS interval and T-wave changes 3
• Hemolysis in patients with glucose-6-phosphate dehydrogenase deficiency 1
• Rare glucose abnormalities 1

Pregabalin (Lyrica) Side Effects

While the provided evidence focuses on hydroxychloroquine, pregabalin commonly causes:

• Dizziness and drowsiness
• Peripheral edema
• Weight gain
• Confusion and cognitive impairment
• Blurred vision

Combined Use Considerations

Additive CNS Depression:

• Both medications can cause dizziness, confusion, and cognitive impairment
• The combination may increase risk of falls, particularly in elderly patients
• Monitor closely for excessive sedation or mental status changes

Overlapping Visual Effects:

• Both drugs can cause blurred vision
• Patients should be counseled about this potential additive effect

Drug Interaction Monitoring:

• Hydroxychloroquine has potentially significant interactions with D-penicillamine and cimetidine, leading to higher drug levels 3, 2
• No direct pharmacokinetic interaction between pregabalin and hydroxychloroquine is documented

Key Monitoring Recommendations

For Hydroxychloroquine:

• Baseline and periodic ECG monitoring, especially if other cardiac risk factors present 2
• Ophthalmologic examinations every 6-12 months 3, 2, 5
• Monitor for psychiatric symptoms, particularly in first weeks of therapy 4
• Assess for dermatologic reactions 6

Common Pitfalls to Avoid:

• Failing to obtain baseline ophthalmologic examination before long-term hydroxychloroquine therapy 2
• Not monitoring ECG when combining hydroxychloroquine with other medications that prolong QT interval 2
• Dismissing early neuropsychiatric symptoms as unrelated to medication 4
• Continuing therapy despite early signs of retinopathy, which may be reversible if caught early 8