NutriStack
Hydrochlorothiazide and Lithium, a caution.
Thiazide diuretics reduce lithium clearance by 25-40%, significantly increasing the risk of lithium toxicity. This is one of the most well-documented drug-drug interactions involving lithium.
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
- Hydrochlorothiazide and Lithium
- Pair type
- Caution
- Evidence (highest tier)
- Strong
- Source citations
- 1 source
- Stack Score effect
- −5 to your Stack Score (per scored caution row).
- Scope
- Supplement × Prescription
- Last verified
- May 30, 2026
Caution · Strong evidence
Caution
What is happening. Thiazide diuretics reduce lithium clearance by 25-40%, significantly increasing the risk of lithium toxicity. This is one of the most well-documented drug-drug interactions involving lithium.
Mechanism. Thiazide diuretics cause sodium and volume depletion. The kidney compensates by increasing proximal tubular sodium reabsorption, and lithium is reabsorbed along with sodium, raising serum lithium levels.
Recommendation. If combination is necessary, reduce lithium dose by 25-50% and monitor lithium levels frequently (weekly initially). Use lowest effective diuretic dose.
Sources (1)
Stack Score
How this pair moves the number.
Effect on the composite score
If both Hydrochlorothiazide and Lithium 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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