Tacrolimus (FK506)
Tacrolimus is a potent macrolide immunosuppressant and calcineurin inhibitor. It inhibits T-lymphocyte activation, suppressing the immune response to protect transplanted organs. Due to its narrow therapeutic index, dosage must be precisely monitored and adjusted based on whole blood trough levels to prevent toxicity or organ rejection.
Dosage by Body Weight
Dosage is highly individualized and must be managed by a transplant specialist. It is typically administered twice daily (every 12 hours) for immediate-release formulations, or once daily for extended-release formulations. Food significantly decreases bioavailability, so it should be taken consistently either always with or always without food. Avoid grapefruit and grapefruit juice as they can increase drug levels to toxic amounts.
- Body Weight
- Below 5 kg
- Dose
- Individualized pediatric starting dose (typically 0.1 to 0.3 mg/kg/day)
- Frequency
- Divided into 2 doses (every 12 hours)
- Tracking Notes
- Requires intensive therapeutic drug monitoring (TDM) to adjust doses based on blood trough levels.
- Body Weight
- 5-7 kg
- Dose
- 0.1 to 0.3 mg/kg/day
- Frequency
- Divided into 2 doses (every 12 hours)
- Tracking Notes
- Titrate dose to achieve target whole blood trough concentrations (typically 5 to 20 ng/mL depending on post-transplant period).
- Body Weight
- 8-10 kg
- Dose
- 0.1 to 0.3 mg/kg/day
- Frequency
- Divided into 2 doses (every 12 hours)
- Tracking Notes
- Monitor renal function, blood pressure, and blood glucose levels regularly during therapy.
- Body Weight
- 11-15 kg
- Dose
- 0.1 to 0.3 mg/kg/day
- Frequency
- Divided into 2 doses (every 12 hours)
- Tracking Notes
- Dosing requirements on a mg/kg basis are often higher in pediatric patients than in adults to achieve similar blood trough levels.
- Body Weight
- 16-20 kg
- Dose
- 0.1 to 0.3 mg/kg/day
- Frequency
- Divided into 2 doses (every 12 hours)
- Tracking Notes
- Maintain strict adherence to dosing times. Never double doses if a dose is missed.
| Body Weight | Dose | Frequency | Tracking Notes |
|---|---|---|---|
| Below 5 kg | Individualized pediatric starting dose (typically 0.1 to 0.3 mg/kg/day) | Divided into 2 doses (every 12 hours) | Requires intensive therapeutic drug monitoring (TDM) to adjust doses based on blood trough levels. |
| 5-7 kg | 0.1 to 0.3 mg/kg/day | Divided into 2 doses (every 12 hours) | Titrate dose to achieve target whole blood trough concentrations (typically 5 to 20 ng/mL depending on post-transplant period). |
| 8-10 kg | 0.1 to 0.3 mg/kg/day | Divided into 2 doses (every 12 hours) | Monitor renal function, blood pressure, and blood glucose levels regularly during therapy. |
| 11-15 kg | 0.1 to 0.3 mg/kg/day | Divided into 2 doses (every 12 hours) | Dosing requirements on a mg/kg basis are often higher in pediatric patients than in adults to achieve similar blood trough levels. |
| 16-20 kg | 0.1 to 0.3 mg/kg/day | Divided into 2 doses (every 12 hours) | Maintain strict adherence to dosing times. Never double doses if a dose is missed. |
Formulation
Purpose
Primarily used to prevent organ rejection in patients receiving allogeneic kidney, liver, or heart transplants. It is also used topically for moderate-to-severe atopic dermatitis and off-label for certain autoimmune conditions.
Generic Name
TacrolimusBranded Drug Names
Tacrolimus (FK506) is listed as a generic drug name. Common branded medicines that may contain the same active ingredient include:
Scheduled Drug
Yes. This medicine should be supplied or used only according to applicable prescription and regulatory requirements.