Furosemide vs Chlorthalidone: side effects in FDA adverse event reports
At a glance
| Furosemide | Chlorthalidone | |
|---|---|---|
| Drug class | Loop Diuretic | Thiazide-like Diuretic |
| Brand names | – | – |
| FAERS reports | 398,182 | 11,542 |
| Serious | 81% | 63% |
| Death outcome | 61,850 | 690 |
| Boxed warning | No | No |
Signals both drugs share
| Reaction | Furosemide | Chlorthalidone | Label screen (A / B) |
|---|---|---|---|
| End stage renal disease | 3,380 · PRR 11.6 | 116 · PRR 11.5 | Labeled (related wording) / Not in label — unassessed |
| Hyperparathyroidism secondary | 895 · PRR 28.4 | 43 · PRR 31.4 | Not in label — unassessed / Labeled (related wording) |
| Metabolic alkalosis | 428 · PRR 19.0 | 15 · PRR 17.2 | Labeled (related wording) / Labeled (related wording) |
| Nephrogenic anaemia | 1,661 · PRR 28.7 | 88 · PRR 34.8 | Likely indication confounding / Likely indication confounding |
| Rebound acid hypersecretion | 701 · PRR 15.4 | 36 · PRR 21.6 | Not in label — unassessed / Not in label — unassessed |
| Chronic kidney disease-mineral and bone disorder | 367 · PRR 26.9 | 32 · PRR 55.7 | Not in label — unassessed / Not in label — unassessed |
Labeled signals distinctive to Furosemide
- Orthostatic hypotension — n=2,320, PRR 7.9 Labeled adverse reaction
Labeled signals distinctive to Chlorthalidone
- Chronic kidney disease — n=460, PRR 11.0 Labeled (related wording)
- Hyponatraemia — n=298, PRR 9.7 Labeled adverse reaction
Common questions
Which has more reported side effects, Furosemide or Chlorthalidone?
Furosemide has 398,182 FAERS reports and Chlorthalidone 11,542. More reports does not mean more dangerous: volume follows how widely and how long a drug has been used, prescription vs over-the-counter status, and publicity. The seriousness share (81% vs 63%) is a better like-for-like signal of the kind of problems reported.
Which side effects do Furosemide and Chlorthalidone share?
Both drugs carry disproportionality signals for end stage renal disease, hyperparathyroidism secondary, metabolic alkalosis, nephrogenic anaemia, rebound acid hypersecretion. Shared signals often reflect a shared drug class or the condition both are used for.
Is Furosemide or Chlorthalidone safer?
FAERS cannot answer that: it has no denominator and no comparator. Use this page to see which risks are already on each label and which signals are unlabeled, then check the prescribing information and your clinician for your situation.
Sources: openFDA FAERS pair statistics (OpenPV build 2026-09-14), FDA labels via openFDA, openFDA count queries for seriousness and deaths. Pair chosen because it is a commonly searched comparison. Generated 2026-10-08.