Supplement × Prescription·a caution·Emerging evidence
L-theanine may compound mild antihistamine-related fatigue or reduced alertness.
Every entry follows the same shape: what is happening, the mechanism, and the recommendation.
What is happening. L-theanine may compound mild antihistamine-related fatigue or reduced alertness.
Mechanism. Potential additive calming effect.
Recommendation. Avoid stacking calming supplements if desloratadine causes drowsiness.
Effect on the composite score
If both Desloratadine and L-Theanine 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 at /methodology/stack-score.
Every claim on this page is cited. PMIDs link straight to PubMed.
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NutriStack is an informational and organizational tool, not a medical service, and not a substitute for professional advice. Always consult a qualified healthcare professional before starting, stopping, or changing any supplement or medication.
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