Neither pregabalin nor gabapentin are established causes of drug-induced lichen planus
Based on the available evidence, neither pregabalin nor gabapentin appear in the documented list of medications that cause drug-induced lichen planus. In fact, these medications are used to treat symptoms associated with lichen planus, not cause it.
Evidence from Drug-Induced Lichen Planus Literature
The established causative drugs for lichen planus include 1:
- Beta-blockers (sufficient evidence with 5+ cases)
- Methyldopa
- Penicillamine
- Quinidine and quinine
- ACE inhibitors (insufficient but suggestive evidence)
- NSAIDs (probably causative based on epidemiologic evidence)
- Hydroxychloroquine
- TNF inhibitors
- Checkpoint inhibitors (most frequently reported in recent literature at 42.1% of cases) 2
- Tyrosine kinase inhibitors (12% of cases) 2
Recent comprehensive reviews of drug-induced lichenoid eruptions 2 analyzing 323 cases over 20 years make no mention of gabapentin or pregabalin as causative agents.
Gabapentin and Pregabalin as Treatment, Not Cause
Paradoxically, these medications are recommended for treating lichen planus-related symptoms:
- For severe pruritus in Grade 3 immune checkpoint inhibitor-related lichen planus: Gabapentin or pregabalin are specifically recommended 3
- For pruritus without rash: Gabapentin, pregabalin, aprepitant, or dupilumab may be used 3
- For lichen simplex chronicus: Gabapentin has shown good response in treating this related condition 4
Clinical Context
The FDA labels for pregabalin 5 list numerous adverse effects including:
- Skin sores (observed in animal studies, though not increased in human trials)
- Weight gain
- Edema
- Dizziness and somnolence
However, lichen planus is not listed as an adverse effect in the pregabalin drug label, despite extensive safety documentation.
Important Caveat
While beta-blockers like bisoprolol are established causes of drug-induced lichen planus 6, and recent concerns about nitrosamine contamination in certain medications (including some beta-blockers) have been raised regarding progression to oral leukoplakia and carcinoma 6, this does not extend to gabapentin or pregabalin.
If a patient develops lichen planus while taking gabapentin or pregabalin, look for other causative medications (particularly beta-blockers, ACE inhibitors, NSAIDs, or immunotherapy agents) rather than attributing it to these GABA analogs.