Resistant hypertension during antituberculosis treatment: how is rifampicin implicated?

Area of Science:

• Pharmacology
• Infectious Diseases
• Cardiology

Background:

• A 67-year-old male with well-controlled hypertension on amlodipine was treated for pulmonary tuberculosis.
• Pulmonary tuberculosis management requires effective antitubercular therapy.

Observation:

• Antitubercular treatment initiated with rifampicin led to suboptimal blood pressure control.
• Antihypertensive regimen escalated to six medications to manage rising blood pressure.

Findings:

• Blood pressure normalized after completion of antitubercular treatment, allowing reduction to two antihypertensives.
• Rifampicin likely attenuated amlodipine's effect via CYP3A4 induction, but other interactions may be involved.

Implications:

• Clinicians should monitor blood pressure closely in hypertensive patients receiving rifampicin-containing regimens.
• Potential drug-drug interactions between antitubercular drugs and antihypertensives require further investigation.
• Consideration of alternative antitubercular agents or closer antihypertensive monitoring may be necessary.