Does Allopurinol Increase Blood Pressure?
No, allopurinol does not increase blood pressure in a 67-year-old healthy male—in fact, it appears to lower blood pressure modestly, particularly at higher doses (≥300 mg daily). 1, 2
Evidence for Blood Pressure Reduction
The most robust evidence demonstrates that allopurinol is associated with blood pressure reduction in older adults with hypertension:
In adults over 65 years with hypertension, allopurinol initiation was associated with a small but significant reduction in both systolic and diastolic blood pressure (approximately 2.1 mm Hg systolic and 1.7 mm Hg diastolic) compared to controls. 1
Higher doses of allopurinol (≥300 mg daily) showed a trend toward greater blood pressure reduction than lower doses. 1
In hemodialysis patients with hyperuricemia, allopurinol 100 mg daily for 12 weeks significantly reduced systolic blood pressure by 15.8% (139 to 117 mm Hg) and diastolic blood pressure by 8.6% (81 to 74 mm Hg). 3
Cardiovascular Benefits in Older Adults
Beyond blood pressure effects, allopurinol demonstrates cardiovascular protective effects in the target age group:
In adults over 65 years with hypertension, allopurinol use was associated with a 50% lower risk of stroke (HR 0.50) and a 39% lower risk of cardiac events (HR 0.61) compared to non-exposed patients. 2
High-dose allopurinol (≥300 mg daily) provided superior cardiovascular protection compared to low-dose treatment in this population. 2
Important Nuance: Age-Dependent Effects
The blood pressure effects of allopurinol appear to differ by age:
In young adults (ages 18-40), a randomized controlled trial found that allopurinol 300 mg daily did not lower systolic blood pressure compared to placebo, despite improving endothelial function (flow-mediated dilation). 4
This suggests the blood pressure-lowering effect is more pronounced in older adults, making it particularly relevant for your 67-year-old patient. 1, 2
Clinical Implications for Your Patient
For a healthy 67-year-old male without hypertension or obesity:
Allopurinol will not cause hypertension and may provide modest blood pressure reduction if prescribed for gout or hyperuricemia. 1
The medication may offer additional cardiovascular protection beyond urate lowering, particularly at standard therapeutic doses (300 mg or higher). 2
Standard dosing can be used without concern for blood pressure elevation; in fact, higher doses appear more beneficial for cardiovascular outcomes. 1, 2
Key Safety Considerations
While blood pressure is not a concern, monitor for the primary serious adverse effect:
The main risk with allopurinol is hypersensitivity syndrome (including Stevens-Johnson syndrome and DRESS), which has a 25% mortality rate. 5
Consider HLA-B*5801 testing before initiation in high-risk populations (Korean patients with CKD stage 3 or worse; Han Chinese and Thai patients). 6
Start at low doses (100 mg daily) and titrate gradually, educating the patient to report any rash immediately. 6, 7