Pregabalin

Evidence Level: L4

Predicted Indications: 10

Pregabalin
Pregabalin: From Anxiety Disorder, Fibromyalgia and Postherpetic Neuralgia to Tendinitis

## Pharmacist Assessment Report

Pregabalin: From Anxiety Disorder, Fibromyalgia and Postherpetic Neuralgia to Tendinitis

One-Sentence Summary

Pregabalin was originally used for anxiety disorder, fibromyalgia, myofascial pain syndrome and postherpetic neuralgia. The TxGNN model predicts it may be effective for tendinitis, but no clinical trials and no direct publications currently support this specific use. The literature found is only indirectly related, so this prediction rests mainly on the computational score.

Quick Overview

Item	Content
Original Indication	Anxiety disorder, fibromyalgia, myofascial pain syndrome, postherpetic neuralgia (from the TxGNN knowledge graph; Singapore licence records list no indication text)
Predicted New Indication	Tendinitis
TxGNN Prediction Score	99.71%
Evidence Level	L4
Singapore Market Status	✓ Marketed
Number of Registrations	20
Recommended Decision	Hold

Why is This Prediction Reasonable?

Detailed mechanism of action data is not available in the compiled data. Pregabalin is known to bind the alpha2-delta subunit of voltage-gated calcium channels. This reduces the release of excitatory neurotransmitters, which may help the neuropathic or centrally sensitized components of pain.

Its original indications (fibromyalgia, myofascial pain, postherpetic neuralgia) are all chronic pain conditions. Tendinitis is a musculoskeletal pain condition, so the model may be picking up this shared pain pathway. Pregabalin could plausibly help where tendon pain has a nerve-related or centrally amplified component.

However, there is no direct evidence in tendinitis. The mechanistic link is a hypothesis, not a demonstrated effect.

Clinical Trial Evidence

Currently no related clinical trials registered.

Literature Evidence

None of these publications studies pregabalin in tendinitis itself. All are indirect.

PMID	Year	Type	Journal	Key Findings
34052386	2022	RCT	Arthroscopy	Perioperative oral pregabalin gave postoperative pain scores equivalent to interscalene nerve block after arthroscopic rotator cuff repair. This is a surgical pain setting, not tendinitis.
32839073	2021	Retrospective cohort	J Orthop Sci	Analgesic and opioid-sparing effect of pregabalin after rotator cuff repair. The abstract notes prior results on opioid sparing were conflicting.
37051935	2023	Case report	Pain Pract	Posterior femoral cutaneous nerve impingement after a marathon, linked to hamstring tendonitis. Does not test pregabalin.
41017607	2025	Case report	Praxis	Fluoroquinolone-associated disability after ciprofloxacin, including tendon problems. An adverse-effect report, not a treatment study.
40818536	2025	Editorial	Arthroscopy	Piriformis syndrome diagnosis and treatment by sciatic neurolysis and piriformis tendon release. Not about pregabalin.
39703364	2024	Preclinical	Adv Pharmacol Pharm Sci	A plant extract reduced vincristine-induced neuropathy in rats. Not about pregabalin or tendinitis.

Singapore Market Information

Pregabalin has 20 valid single-ingredient licences in Singapore, all oral capsules. The licence records contain no approved indication text. Five examples:

Authorization Number	Product Name	Dosage Form	Manufacturer
SIN13097P	Lyrica Capsule 150mg	Capsule	Pfizer Manufacturing Deutschland GmbH
SIN14488P	Brillior Capsule 75mg	Capsule	Pfizer Manufacturing Deutschland GmbH
SIN14489P	Brillior Capsule 150mg	Capsule	Pfizer Manufacturing Deutschland GmbH
SIN15777P	Regadex Capsule 150mg	Capsule	Dexcel Ltd.
SIN15655P	Rewisca Hard Capsules 150mg	Capsule	Krka, d.d., Novo mesto

Safety Considerations

Knowledge-graph contraindication signals (from the TxGNN knowledge graph, not from label text): thrombocytopenia, angioedema (including hereditary, acquired and RAAS-blocker-induced forms), myopathy and muscle diseases (including rhabdomyolysis and familial periodic paralysis), impaired renal function, and atrioventricular block. The graph also lists anxiety disorder and related neurotic and dysthymic disorders, which is unexpected given pregabalin's original use and should be verified against the label.
Drug Interactions: 100 interaction records were found; 20 were reviewed.
- Major: morphine and liposomal morphine, which carry additive CNS and respiratory depression concerns.
- Moderate: opioid and cannabinoid-type agents (opium, difenoxin, diphenoxylate, dronabinol, nabilone), metoclopramide, thiazolidinediones (pioglitazone, rosiglitazone, troglitazone), and sibutramine.
- Several other interactions have unknown severity.

Please refer to the package insert for full warnings and contraindications.

Conclusion and Next Steps

Decision: Hold

Rationale: The 99.71% TxGNN score is a computational prediction only. No clinical trials exist for tendinitis, and the few publications found are indirect (post-surgical pain, case reports, an editorial, and a rat study). The mechanistic link through pain modulation is plausible but unproven.

To proceed, the following is needed:

Clinical studies of pregabalin in tendinitis or tendinopathy, preferably randomized and placebo-controlled
Detailed mechanism of action data
Package insert warnings and contraindications for Singapore-registered products
A defined patient population (for example, tendon pain with neuropathic or centrally sensitized features) and a safety plan covering sedation, dizziness, falls, renal dosing and opioid co-use

Note: Two other TxGNN predictions for pregabalin have much stronger supporting evidence than tendinitis. Osteoarthritis (L1, including a 2026 meta-analysis and several Phase 3/4 trials) and headache disorder (L1, including a completed Phase 3 trial in postdural puncture headache) are both rated "Proceed with Guardrails". They may be better candidates to evaluate first.

Disclaimer

This content is for research purposes only and does not constitute medical advice. Clinical validation is required before any clinical application.