Objective. To determine whether a double dose of intraarticular triamcinolone acetonide is more effective for knee arthritis than a 40-mg dose. Methods. In this 12-week randomized controlled clinical trial, 40 mg and 80 mg of intraarticular triamcinolone acetonide were compared in patients with knee arthritis. Evaluated variables included a Likert burden scale, visual analog scale pain scale, degree of arthritis activity, presence of swelling, and presence of functional limitation. Results. Ninety-seven patients were randomized. No significant differences were observed between the groups regarding any outcomes. Conclusion. An 80-mg dose of triamcinolone acetonide had no additional benefit compared with 40 mg as treatment for knee arthritis.