BACKGROUND: de Quervain tenosynovitis usually responds well to nonsurgical treatment.HYPOTHESIS: Growth hormone abuse is associated with increased de Quervain tenosynovitis incidence in weight-training persons.STUDY DESIGN: Cohort study; Level of evidence, 3.METHODS: We treated 19 weight-training male patients with de Quervain tenosynovitis. Nine were abusing growth hormone (group A), and 10 were not (group B). Four group A patients elected to cease growth hormone abuse. Treatment was stratified into 3 grades: (1) splinting and nonsteroidal anti-inflammatory drugs, (2) same as first grade but with the addition of cortisone injections, and (3) surgical decompression (after failure of treatment of first and second grades). Follow-up was at 3, 9, and 24 months.RESULTS: First follow-up: Only 33.3% of those using growth hormone in group A responded to splinting and nonsteroidal anti-inflammatory drugs, compared with 90% in group B. Six patients (66.6%) in group A experienced persistent symptoms and received second-grade treatment, compared with 1 patient in group B (10%). Second follow-up: Four patients (44.4%) in group A moved from second- to third-grade treatment, 1 symptom-free patient (11.1%) relapsed and received second-grade treatment while 2 (22.2%) requested conservative treatment, declining surgery. Group B patients were 100% symptom-free. Final follow-up: Six patients (66.6%) in group A were operated on and 1 (11.1%) suffered from persistent de Quervain tenosynovitis, declining surgery. In group B, 1 patient relapsed and was started on second-grade treatment. No patients in group B had surgery.CONCLUSION: Our results suggest that growth hormone abuse is associated with a more recalcitrant form of de Quervain tenosynovitis that does not respond well to nonsurgical treatment, thus leading to increased likelihood of surgical decompression.