Sulfamethoxazole and Trimethoprim vs Doxycycline: side effects in FDA adverse event reports
At a glance
| Sulfamethoxazole and Trimethoprim | Doxycycline | |
|---|---|---|
| Drug class | Sulfonamide Antimicrobial, Dihydrofolate Reductase Inhibitor Antibacterial | Tetracycline-class Drug |
| Brand names | – | – |
| FAERS reports | 83,846 | 67,795 |
| Serious | 83% | 72% |
| Death outcome | 10,343 | 6,693 |
| Boxed warning | No | No |
Signals both drugs share
| Reaction | Sulfamethoxazole and Trimethoprim | Doxycycline | Label screen (A / B) |
|---|---|---|---|
| Sleep disorder due to general medical condition, insomnia type | 1,017 · PRR 46.8 | 892 · PRR 49.6 | Labeled (related wording) / Labeled (related wording) |
| Rheumatic fever | 489 · PRR 31.4 | 1,095 · PRR 103.5 | Labeled adverse reaction / Not in label — unassessed |
| Folliculitis | 1,384 · PRR 38.6 | 1,200 · PRR 40.6 | Not in label — unassessed / Not in label — unassessed |
| Hand deformity | 1,056 · PRR 21.9 | 1,271 · PRR 33.2 | Not in label — unassessed / Not in label — unassessed |
| Helicobacter infection | 1,023 · PRR 27.8 | 1,281 · PRR 44.4 | Not in label — unassessed / Not in label — unassessed |
| Duodenal ulcer perforation | 1,015 · PRR 40.0 | 1,219 · PRR 61.5 | Not in label — unassessed / Not in label — unassessed |
| Muscle injury | 1,202 · PRR 42.8 | 872 · PRR 36.7 | Not in label — unassessed / Not in label — unassessed |
| Deep vein thrombosis postoperative | 305 · PRR 45.9 | 869 · PRR 247.6 | Not in label — unassessed / Not in label — unassessed |
| Facet joint syndrome | 362 · PRR 32.3 | 710 · PRR 89.9 | Not in label — unassessed / Not in label — unassessed |
| Adjustment disorder with depressed mood | 271 · PRR 38.7 | 510 · PRR 104.8 | Not in label — unassessed / Not in label — unassessed |
| Dislocation of vertebra | 250 · PRR 31.6 | 456 · PRR 79.7 | Not in label — unassessed / Not in label — unassessed |
| Lupus vulgaris | 122 · PRR 28.5 | 509 · PRR 232.4 | Likely indication confounding / Not in label — unassessed |
| Retinitis | 106 · PRR 16.9 | 409 · PRR 100.4 | Not in label — unassessed / Not in label — unassessed |
| Subcutaneous drug absorption impaired | 96 · PRR 53.4 | 50 · PRR 31.2 | Not in label — unassessed / Not in label — unassessed |
Labeled signals distinctive to Sulfamethoxazole and Trimethoprim
- Neuritis — n=106, PRR 18.4 Labeled adverse reaction
Labeled signals distinctive to Doxycycline
- Autoimmune disorder — n=890, PRR 31.6 Labeled (related wording)
Common questions
Which has more reported side effects, Sulfamethoxazole and Trimethoprim or Doxycycline?
Sulfamethoxazole and Trimethoprim has 83,846 FAERS reports and Doxycycline 67,795. 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 (83% vs 72%) is a better like-for-like signal of the kind of problems reported.
Which side effects do Sulfamethoxazole and Trimethoprim and Doxycycline share?
Both drugs carry disproportionality signals for sleep disorder due to general medical condition, insomnia type, rheumatic fever, folliculitis, hand deformity, helicobacter infection. Shared signals often reflect a shared drug class or the condition both are used for.
Is Sulfamethoxazole and Trimethoprim or Doxycycline 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.