NutriStack
Pine Bark Extract and Tamsulosin, a caution.
Tamsulosin can cause orthostatic hypotension, especially when it is started or restarted. Pine bark extract products such as pycnogenol have shown modest blood-pressure-lowering effects in some meta-analyses. Combining them may increase dizziness, near-fainting, or fall risk in people with low baseline blood pressure, dehydration, or other blood pressure medicines.
One pair, every claim cited. The two substances, the type, the mechanism, the recommendation, and the primary literature.
Same shape as the other 1,729 pairs in the public database.
From the interaction database
What the row says.
Every entry follows the same shape: what is happening, the mechanism, the recommendation, and the primary literature.
At a glance
- Substances
- Pine Bark Extract and Tamsulosin
- Pair type
- Caution
- Evidence (highest tier)
- Emerging
- Source citations
- 2 sources
- Stack Score effect
- −5 to your Stack Score (per scored caution row).
- Scope
- Supplement × Prescription
- Last verified
- May 30, 2026
Caution · Emerging evidence
Caution
What is happening. Tamsulosin can cause orthostatic hypotension, especially when it is started or restarted. Pine bark extract products such as pycnogenol have shown modest blood-pressure-lowering effects in some meta-analyses. Combining them may increase dizziness, near-fainting, or fall risk in people with low baseline blood pressure, dehydration, or other blood pressure medicines.
Mechanism. Tamsulosin can reduce vascular alpha1-mediated compensation during standing despite its uroselectivity. Pine bark polyphenols may improve endothelial nitric-oxide signaling and modestly reduce systolic and diastolic pressure, creating additive hypotension risk.
Recommendation. Do not start pine bark extract at the same time you start or restart tamsulosin. If you use both, begin with a low pine bark dose, check sitting and standing blood pressure for 1-2 weeks, and stop the supplement if lightheadedness occurs.
Sources (2)
- Bird ST, Delaney JA, Brophy JM, Etminan M, Skeldon SC, Hartzema AG. Tamsulosin treatment for benign prostatic hyperplasia and risk of severe hypotension in men aged 40-85 years in the United States: risk window analyses using between and within patient methodology. BMJ. 2013;347:f6320. PMID 24192967
- Malekahmadi M, Moradi Moghaddam O, Firouzi S, Daryabeygi-Khotbehsara R, Islam SMS, Norouzy A, Soltani S. Effects of pycnogenol on cardiometabolic health: A systematic review and meta-analysis of randomized controlled trials. Pharmacol Res. 2019;150:104472. PMID 31585179
Stack Score
How this pair moves the number.
Effect on the composite score
If both Pine Bark Extract and Tamsulosin are in the same stack, this pair applies −5 to your Stack Score (per scored caution row).
The full algorithm, the clamping rules, and four worked stacks are documented at /methodology/stack-score.
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