Short answer: It may raise the risk of sudden kidney injury in some men. In TRAVERSE, acute kidney injury was reported in 2.3% of men on testosterone gel against 1.5% on placebo, and the AndroGel 1.62% and Xyosted labels now list it. A record-based study of similar men found 1.53 times the risk. No study has shown why, and the labels say testosterone was not studied in kidney impairment.
TRAVERSE gave 1.62% testosterone gel or placebo gel to men aged 45 to 80 with low testosterone and heart disease or high heart risk (Lincoff 2023). Its main result was that heart attacks, strokes and heart deaths were not more common on testosterone. The paper also reported a higher incidence of atrial fibrillation, acute kidney injury and pulmonary embolism in the testosterone group.
| Event | Testosterone gel | Placebo |
|---|---|---|
| Acute kidney injury | 2.3% | 1.5% |
| Atrial fibrillation | 3.5% | 2.4% |
| Non-fatal arrhythmias needing treatment | 5.2% | 3.3% |
| Bone fracture | 3.5% | 2.5% |
The trial was not designed to explain the kidney finding. It used daily gel in men with heart risk, so it does not show the rate with injections or in younger, healthier men. The heart rhythm result is covered in atrial fibrillation on TRT.
Greenberg 2024 used health records to match 2,134 men aged 45 to 80 with testosterone of 100 to 300 ng/dL who were prescribed testosterone gel with 2,134 similar men who were not. Over 3 years, acute kidney injury was more common on testosterone (relative risk 1.53, range 1.07 to 2.18). The authors noted the study looked back at claims data, which has limits, and called for more research.
The AndroGel 1.62% label says no studies were done in people with kidney impairment (section 8.6). It warns that testosterone can make the body hold salt and water, and that swelling, with or without heart failure, may be a serious complication in people with existing heart, kidney or liver disease (section 5.10). Taking testosterone with corticosteroids can add to fluid retention (section 7.3). More on this is in swelling on TRT.
MedlinePlus lists symptoms of acute kidney failure that include passing little or no urine, swelling in the legs, ankles and feet, tiredness, nausea or vomiting, and flank pain. Common causes include dehydration, NSAID pain relievers, some blood pressure medicines and contrast dye. Kidney function is checked with blood tests such as creatinine and BUN; creatine supplements can raise creatinine, covered in creatine and kidney tests.
Whether kidney tests belong in routine TRT bloodwork is for the prescriber to decide. Dose Track can keep creatinine and eGFR results next to each dose, so a change is easy to spot.
Read more on Dose Track: Low testosterone · AndroGel side effects · eGFR · TRT hematocrit monitoring