คำอธิบาย
Combining sildenafil with nitrates causes profound, potentially fatal hypotension; this combination is absolutely contraindicated.
กลไก
Nitrates increase cyclic GMP via guanylate cyclase stimulation, causing vascular smooth muscle relaxation; sildenafil inhibits PDE5, preventing cGMP degradation. The combined effect causes an uncontrolled and potentially catastrophic reduction in blood pressure.
ความสำคัญทางคลินิก
Mean blood pressure drops of >25 mmHg have been documented; cardiovascular collapse, syncope, MI, and death have been reported with concurrent use.
การจัดการ
Absolute contraindication. Patients who use sildenafil for erectile dysfunction must be counseled to avoid ALL nitrate forms (sublingual, oral, transdermal, IV). If nitrate use is necessary after sildenafil, wait at least 24 hours (48 hours for tadalafil).
ข้อจำกัดความรับผิดชอบทางการแพทย์
This content is for educational and informational purposes only. It is not a substitute for professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider before making medication decisions.