Tirosint Formulations
Tirosint does NOT come in traditional tablet form—it is available as a soft gelatin capsule and as an oral solution (Tirosint-SOL). 1, 2
Available Formulations
Soft Gelatin Capsules: Tirosint is manufactured as levothyroxine in a soft gel capsule formulation, which differs from conventional compressed tablets 2, 3
Oral Solution (Tirosint-SOL): This liquid formulation contains only three ingredients—levothyroxine, purified water, and glycerol—and gained FDA approval in 2017 2, 4
NOT Available as Tablets: Unlike standard levothyroxine products (such as Synthroid or generic levothyroxine), Tirosint is specifically formulated to avoid the tablet form 2
Why the Formulation Matters
The soft gel and liquid formulations offer distinct advantages over tablets, particularly for patients with absorption issues:
Superior Absorption with Proton Pump Inhibitors (PPIs): In thyroidectomized patients taking PPIs, switching from conventional levothyroxine tablets to Tirosint soft capsules at the same dose resulted in significantly decreased TSH (-0.68 mIU/L at 12 weeks) and increased thyroid hormone levels, indicating better absorption despite PPI use 3
Effective in Malabsorption Conditions: Liquid levothyroxine formulations are more effective than tablets in patients with malabsorption caused by interfering diseases, drugs, and bariatric surgery 2
Minimal Excipients: The soft gel capsule contains fewer inactive ingredients than tablets, making it advantageous for patients with multiple food and medication sensitivities 4
Flexible Timing: Liquid levothyroxine appears equally effective when taken before or during breakfast, unlike tablets which require strict fasting 2
Clinical Implications
For patients with hypothyroidism who specifically request "Tirosint tablets," clarify that:
- Tirosint only comes as soft gel capsules or oral solution 2
- If they need a tablet formulation, they would require a different levothyroxine brand (such as Synthroid, Levoxyl, or generic levothyroxine tablets) 1
- The soft gel or liquid formulations may actually provide better thyroid control than tablets, particularly in patients with gastrointestinal conditions, those taking PPIs or antacids, or those with absorption issues 2, 3
Special Populations
Neonates: Liquid levothyroxine showed higher incidence of TSH suppression compared to tablet formulations, requiring particular attention to avoid overtreatment 2
Patients with Gastroparesis and SIBO: A patient with Hashimoto's disease, gastroparesis, and small intestinal bacterial overgrowth achieved normalized TSH levels only after switching to Tirosint-SOL, when both tablets and compounded suspensions had failed 4
Enteral Tube Feeding: Liquid levothyroxine is effective and easy to handle in patients fed by enteric tube 2