Abstract: Objective: To discuss the diagnosis and treatment process of abnormally elevated blood pressure in the patient treated with rifampicin and antihypertensive drugs, to analyze the interaction between rifampicin and antihypertensive drugs, and to improve the clinicians' understanding of the administration in the patients.Methods: The clinical materials of a patient treated with rifampicin and antihypertensive drugs were collected,and the relationship between the blood pressure change and drug was analyzed.The changes of concentrations of dihydropyridine-based calcium antagonists after administration of rifampin were observed and the relative literatures were reviewed.Results: A 58-year-old man with coughing and coughing for 1 month was admitted to hospital.The patient was definitely diagnosed as tuberculosis and hypertension before admission;the patient was treated with rifampicin, isoniazid, ethambutol, pyrazinamide, and felodipine together.The original treatment plan was continued and the blood pressure of the patient was monitored.On the 9th day of anti-tuberculosis treatment, the patient developed dizziness, chest tightness, and severe fluctuations in blood pressure.Then rifampicin was stopped and antihypertensive drugs were adjusted.At the beginning of blood pressure fluctuation of the patient, the combination of angiotensin-converting enzyme inhibitors and the increasing dose of dihydropyridine-based calcium antagonists did not control the blood pressure.The blood pressure began to decrease significantly at 36 h after rifampin was stopped.On the 18th day of anti-tuberculosis treatment, the original antihypertensive plan was restored and the blood pressure remained stable.Conclusion: Rifampicin can sometimes significantly reduce the effect iveness of antihypertensive drugs (such as dihydropyridine calcium antagonists), and the clinicians should pay attention to it.

Key words: rifampin, hypertension, felodipine, benazepril hydrochloride, amlodipine besylate, case report