Tofacitinib is an oral small molecule Janus kinase (JAK) inhibitor that regulates immune cell activity and inflammatory response by selectively inhibiting the JAK-STAT signaling pathway.

1、 Drug name

1. Common name: Tofacitinib

2. Product Name: XELJANZ ®

2、 Indications

1. Rheumatoid arthritis: Used for adult patients with moderate to severe activity who have insufficient or intolerable efficacy of methotrexate.

2. Psoriatic arthritis: Used for adult active patients with insufficient or intolerable efficacy of methotrexate or other anti rheumatic drugs to improve the condition.

3. Ulcerative colitis: Used for adult patients with moderate to severe active disease who have insufficient or intolerable efficacy of tumor necrosis factor inhibitors.

4. Multi joint juvenile idiopathic arthritis: used for active patients aged 2 years and above.

3、 Specifications and characteristics

5 milligrams: tablets.

4、 Main components

1. Active ingredient: Tofacitinib citrate.

2. Auxiliary materials: Various tablets and oral solutions contain different auxiliary materials, such as lactose, cellulose, titanium dioxide, polyethylene glycol, etc.

5、 Usage and dosage

1. Rheumatoid arthritis/psoriatic arthritis: Tofacitinib 5mg twice daily, or Tofacitinib XR11mg once daily.

2. Ulcerative colitis:

Induction therapy: Tofacitinib 10mg twice daily or XR22mg once daily, lasting for at least 8 weeks and up to 16 weeks.

Maintenance therapy: Tofacitinib 5mg twice daily or XR11 mg once daily.

Juvenile idiopathic arthritis: adjust the dosage according to body weight, take orally twice a day.

6、 Dose adjustment

1. For patients with moderate to severe kidney function impairment or moderate liver function impairment: Tofacitinib 5mg once daily is recommended.

2. Severely impaired liver function: Not recommended for use.

3. Those who use strong CYP3A4 inhibitors or intermediate acting CYP3A4 combined with strong CYP2C19 inhibitors: need to reduce dosage.

4. When there is a decrease in lymphocytes, neutrophils, or anemia: the dosage needs to be interrupted or adjusted.

7、 Medication precautions

1. Medication time: Regular tablets and oral solution twice a day, sustained-release tablets once a day, can be taken with food or alone.

2. Omission treatment: Take the medication as soon as possible. If it is close to the next dose, skip it and do not double the dosage.

3. Vomiting after taking medication: If vomiting occurs shortly after taking medication, it is not recommended to take it again. You should wait until the next scheduled time to take the medication.

4. Sustained release tablets should be swallowed whole and should not be crushed, split, or chewed. It is normal to see a complete empty shell in the feces after taking medication.

8、 Medication for special populations

1. Pregnant woman: There is insufficient data available, it is recommended to inform the doctor.

2. Breastfeeding period: It is not recommended to breastfeed during medication and after the last dose.

3. Children: Oral solution is only approved for children aged 2 years and above with idiopathic arthritis.

4. Elderly people (≥ 65 years old): have a higher risk of infection and should be used with caution.

5. Patients with liver and kidney dysfunction: moderate to severe damage requires dose adjustment, and severe liver damage is contraindicated.

9、 Adverse reactions

Common adverse reactions include:

1. Upper respiratory tract infection, nasopharyngitis, headache, diarrhea.

2. Elevated blood lipids, elevated blood pressure, and elevated creatine kinase.

3. The risk of herpes zoster infection increases.

4. Serious infections, malignant tumors, blood clots, gastrointestinal perforation, etc. are potential serious adverse reactions.

10、 Contraindications

1. There are no absolute contraindications, but treatment should not be initiated or interrupted when the following conditions exist:

2. Active severe infection.

3. Lymphocyte count<500 cells/mm ³, neutrophil count<1000 cells/mm ³, hemoglobin<9 g/dL.

11、 Drug interactions

1. Avoid co administration with strong CYP3A4 inducers (such as rifampicin) as it may reduce efficacy.

2. When used in combination with strong CYP3A4 inhibitors (such as ketoconazole) or medium acting CYP3A4+strong CYP2C19 inhibitors (such as fluconazole), dosage reduction is required.

3. It is not recommended to use it in combination with biologics or strong immunosuppressants such as azathioprine and cyclosporine.

12、 Storage method

Tablets: Store at 20 ° C-25 ° C.

Tofacitinibinformation