AndroGel Geriatric (65+) Safety: What Older Men and Their Doctors Need to Know

What Is AndroGel and Why Is It Prescribed in Older Men?

AndroGel delivers exogenous testosterone through the skin and is indicated for confirmed male hypogonadism: a total serum testosterone below roughly 300 ng/dL on two morning measurements, combined with signs or symptoms such as reduced libido, fatigue, or loss of muscle mass. Prevalence of low serum testosterone rises with age. Cross-sectional data from the Massachusetts Male Aging Study found that total testosterone falls at approximately 1.6% per year after age 40, and free testosterone falls even faster, making hypogonadism substantially more common after 65 than in younger decades [1].

The T-Trials (Testosterone Trials), a coordinated set of seven placebo-controlled trials enrolling 788 men aged 65 or older with confirmed hypogonadism (mean baseline serum T approximately 234 ng/dL), established that transdermal testosterone raised serum T into the mid-normal range, improved sexual function scores, and modestly improved bone density and walking distance [2]. Symptomatic benefit was real. So were the safety signals, which is precisely why prescribing in this age group demands more caution than in men aged 30 to 50.

Age changes several things that affect how AndroGel behaves in the body. Skin thickness and subcutaneous blood flow both decrease with age, potentially altering absorption variability. Serum albumin and sex hormone-binding globulin concentrations shift, changing the free-to-total testosterone ratio. Renal clearance of metabolites declines. Each of these factors means that a dose producing a mid-normal serum T level in a 45-year-old may produce a supratherapeutic level in a 72-year-old using the same gram-per-day amount.

Cardiovascular Safety: What the Evidence Actually Shows

Cardiovascular risk in older men on testosterone therapy is the most contested area of the evidence base. The FDA issued a safety communication in 2015 requiring manufacturers to add language about a possible increased risk of myocardial infarction and stroke to all testosterone product labels, based on observational data and two small randomized trials [3]. The picture has grown more nuanced since then.

The T-Trials cardiovascular sub-trial found that men randomized to testosterone had a greater increase in non-calcified coronary artery plaque volume at 12 months compared with placebo (from 204 to 232 mm³ vs. 317 to 325 mm³; between-group difference 41 mm³, 95% CI 14 to 67 mm³; P<0.001) [4]. Plaque volume is a surrogate endpoint, not a direct measure of myocardial infarction rates, but the finding was enough to prompt formal evaluation.

The TRAVERSE trial (N=5,246, mean age 63.5 years, all with pre-existing or high risk for cardiovascular disease) reported that testosterone therapy was non-inferior to placebo for major adverse cardiovascular events (MACE) over a median follow-up of 33 months (hazard ratio 0.96 to 95% CI 0.78 to 1.17) [5]. That result is reassuring for MACE, but the same trial found higher rates of atrial fibrillation (3.5% vs. 2.4%), pulmonary embolism (0.9% vs. 0.5%), and acute kidney injury in the testosterone arm [5]. These secondary findings matter in a geriatric population where baseline rates of AF and thromboembolism are already elevated.

Practical guidance from the American Urological Association's 2022 testosterone deficiency guideline states that clinicians should discuss cardiovascular risks explicitly with patients and should avoid initiating testosterone therapy within 6 months of a myocardial infarction or stroke [6]. Men 65+ have higher background rates of both, so the pre-initiation cardiovascular review carries more weight.

Erythrocytosis: The Most Common Serious Lab Abnormality

Testosterone stimulates erythropoiesis. Hematocrit rises are dose-dependent and more pronounced in older men, partly because baseline erythropoietin sensitivity increases with age and partly because older men metabolize androgens differently. The T-Trials reported that 5.7% of men in the testosterone group developed erythrocytosis (hematocrit above 54%) compared with 0% in the placebo group [2].

The AndroGel FDA prescribing information requires measuring hematocrit at baseline, at 3 to 6 months after starting treatment, and annually thereafter. If hematocrit exceeds 54%, the label directs clinicians to withhold treatment until the value drops to an acceptable level, then to restart at a lower dose [7]. Men 65+ who smoke, live at altitude, or have underlying sleep apnea face additional erythrocytosis risk on top of the testosterone-related increment.

Elevated hematocrit raises whole-blood viscosity and has been associated with increased risk of thromboembolic events [8]. In older men who may already have atrial fibrillation or venous insufficiency, erythrocytosis compounds existing risk. Routine monitoring is not optional in this population. It is the minimum standard of care.

Falls and Fracture Risk: A Two-Sided Equation

Testosterone has anabolic effects on skeletal muscle and bone, and those effects could theoretically reduce falls and fractures in hypogonadal older men. The T-Trials bone sub-trial showed that testosterone increased volumetric bone mineral density at the spine by 7.5% and at the hip by 3.4% over 12 months, compared with modest changes in the placebo group [9]. Those are meaningful numbers for a population where hip fracture carries roughly 20 to 30% one-year mortality [10].

The falls picture is less clear-cut. Increased hematocrit can cause dizziness. Dose titration errors or supratherapeutic peaks can cause mood variability or fluid retention. Testosterone may increase red cell mass enough to raise blood pressure modestly, which itself is a falls risk modifier. The functional improvement seen in some T-Trials participants did not translate into statistically significant falls reduction in the trial's physical function sub-analysis [11].

For men 65+ already on antihypertensives, diuretics, or sedatives, adding a drug that changes fluid balance and blood pressure deserves a falls-risk review at initiation and at each monitoring visit. The American Geriatrics Society Beers Criteria list testosterone among medications to use with caution in older adults, citing the cardiovascular and erythrocytosis risks rather than a blanket prohibition [12].

Renal Function Decline and Dose Considerations

Glomerular filtration rate falls by roughly 1 mL/min/1.73 m² per year after age 40 in men without kidney disease. By age 70, a man with no diagnosed renal disease may have a GFR of 55 to 65 mL/min/1.73 m², technically placing him in CKD Stage 2 or early Stage 3 [13]. This matters for testosterone therapy because androgen-related fluid and sodium retention can worsen edema and, in men close to the threshold for dialysis, may precipitate decompensation.

The AndroGel prescribing label does not specify dose adjustments for renal impairment as a standalone instruction, but it does warn about edema with or without congestive heart failure in patients with pre-existing cardiac, renal, or hepatic disease [7]. Clinicians should weigh this against the fact that testosterone-induced muscle preservation may actually slow functional decline in men with CKD-related sarcopenia. A documented conversation about fluid retention risk, with a baseline weight and blood pressure recorded, is good practice before starting therapy in any man with GFR <60 mL/min/1.73 m².

Drug-Drug Interactions in a Polypharmacy Population

Men aged 65 and older take an average of 4.5 prescription medications daily, and roughly 36% take five or more [14]. AndroGel adds to that burden and introduces several clinically meaningful interactions.

Warfarin is the most important. Testosterone potentiates the anticoagulant effect of warfarin by inhibiting its hepatic metabolism, and the AndroGel label carries an explicit warning to monitor INR closely when initiating, changing the dose of, or discontinuing testosterone in men on oral anticoagulants [7]. A single-dose change in the AndroGel regimen can shift INR by 0.5 or more in warfarin-sensitive patients. Men on direct oral anticoagulants (apixaban, rivaroxaban) face less pharmacokinetic interaction, but the additive thromboembolism risk from erythrocytosis still applies.

Insulin sensitivity changes on testosterone. Men with type 2 diabetes on sulfonylureas or insulin should have glucose monitoring intensified at initiation, because improved insulin sensitivity may precipitate hypoglycemia [15]. This is a real clinical concern, not a theoretical one.

Corticosteroids used for chronic inflammatory conditions share fluid-retaining properties with testosterone. Co-administration raises the risk of edema and blood pressure elevation. Oxyphenbutazone, though rarely used today, has a listed interaction. More practically, any NSAID added for arthritis pain in an older man on AndroGel worsens fluid retention risk cumulatively.

The table below outlines a proposed interaction-check framework for men 65+ starting AndroGel. Clinicians should review this list at every medication reconciliation visit.

| Drug Class | Interaction Mechanism | Clinical Action | |---|---|---| | Warfarin | Inhibited CYP2C9 metabolism, raised INR | Check INR within 2 weeks of any dose change | | Insulin / sulfonylureas | Improved insulin sensitivity lowers glucose | Intensify glucose monitoring at initiation | | Systemic corticosteroids | Additive fluid retention, edema | Monitor weight and blood pressure weekly for first month | | NSAIDs | Additive sodium/fluid retention | Prefer acetaminophen for pain; limit NSAID course | | Erythropoiesis-stimulating agents | Additive erythrocytosis | Avoid co-administration unless dialysis-indicated | | Antihypertensives | Fluid retention may blunt effect | Recheck blood pressure at 6-week visit |

Prostate Safety and PSA Monitoring

Prostate-specific antigen should be measured at baseline and at 3 months after starting AndroGel in any man for whom prostate cancer screening is otherwise indicated by age and risk [7]. The 2022 AUA guideline specifies that a PSA rise of more than 1.4 ng/mL above baseline within 12 months, or any single PSA above 4.0 ng/mL, should prompt urologic referral before continuing therapy [6].

Testosterone therapy does not appear to cause de novo prostate cancer based on current evidence, but it may stimulate growth of pre-existing occult disease. Because the prevalence of undiagnosed low-grade prostate cancer in men over 65 ranges from 30 to 50% in autopsy series, this concern is not trivial [16]. A shared decision-making conversation about prostate risk, documented in the chart, is part of appropriate prescribing in this age group.

Benign prostatic hyperplasia symptoms can worsen on testosterone because intraprostatic dihydrotestosterone levels rise. Men 65+ who already use alpha-blockers or 5-alpha-reductase inhibitors for lower urinary tract symptoms need symptom reassessment at the 3-month visit [7].

Transfer Risk and Caregiver Considerations

Older men living with partners, grandchildren, or in assisted-living facilities create a specific transfer risk. Testosterone gel applied to the shoulders or upper arms must dry fully before clothing covers the area, and direct skin-to-skin contact with the application site should be avoided until the next washing [7]. Women who are pregnant or may become pregnant face particular risk from secondary exposure, as testosterone is a known teratogen (FDA pregnancy category X for the indication).

In a geriatric context where a spouse may assist with morning routines, dressing, or bathing, verbal and written counseling on transfer precautions is part of every prescription encounter, not a one-time disclosure at initiation.

Deprescribing: When Stopping Is the Right Decision

Not every man who starts AndroGel in his late 60s should continue it at 78 or 82. Deprescribing testosterone is appropriate when symptomatic benefit cannot be demonstrated after 3 to 6 months of treatment at a therapeutic serum level, when a new cardiovascular contraindication develops, when hematocrit cannot be controlled below 54% with dose reduction, or when the patient's goals of care shift away from longevity-oriented interventions [17].

The Endocrine Society's 2018 clinical practice guideline on testosterone therapy states: "We suggest that clinicians reassess patients for symptom improvement and potential adverse effects after 3 to 6 months of testosterone therapy and then annually" [18]. Absence of documented benefit at a reassessment point is a clinically sound reason to taper and stop.

Tapering is generally not required physiologically, since exogenous testosterone suppresses the hypothalamic-pituitary-gonadal (HPG) axis. Men whose endogenous production was borderline before starting therapy may experience a temporary return to low-normal testosterone levels after stopping that resolves over 3 to 6 months. Men with primary hypogonadism had limited endogenous production to begin with, so the post-discontinuation nadir is their new baseline regardless.

A structured stop trial at 6 months, with serum testosterone and symptom reassessment at 8 weeks post-discontinuation, gives both patient and clinician objective data on whether the drug is providing net benefit.

Monitoring Schedule for Men 65+ on AndroGel

Monitoring in older men should be more frequent than in younger adults, given the faster pace of cardiovascular risk change and the higher likelihood that comorbidities will evolve [6]. The following schedule reflects the AndroGel FDA label combined with AUA 2022 guideline recommendations:

Before starting: Total and free serum testosterone on two separate morning specimens, hematocrit, PSA, digital rectal exam or urology referral if PSA is above 3.0 ng/mL, fasting lipids, blood pressure, and documentation of cardiovascular history.

At 3 to 6 months: Serum testosterone (mid-morning, before gel application that day), hematocrit, PSA (if not done within 3 months), blood pressure, weight, and a structured symptom review using a validated tool such as the Aging Males Symptoms (AMS) scale.

Annually: All of the above, plus a falls-risk screen, a polypharmacy reconciliation, and a re-documented benefit-risk discussion.

If hematocrit rises above 54% at any visit, testosterone should be withheld, the patient evaluated for secondary causes (sleep apnea, smoking, altitude), and therapy restarted at a 25 to 50% lower dose once hematocrit normalizes [7].

Skin Application Technique and Dose Individualization

AndroGel 1% is available in unit-dose packets or a metered-dose pump. The 1.62% formulation delivers a higher testosterone mass per pump actuation (20.25 mg testosterone per actuation) and reaches equivalent serum levels with smaller gel volumes, which may reduce transfer risk. Both formulations are applied once daily to clean, dry, intact skin on the shoulders, upper arms, or abdomen (1% only for abdomen per label).

Older skin may be dryer or more fragile, and abrasions or open areas should not serve as application sites since absorption may be unpredictable. Patients or caregivers who assist with application should wear gloves. Washing hands immediately after application is mandatory regardless of glove use [7].

Serum testosterone should be measured 2 to 8 hours after application to capture the absorption window accurately. A single low reading taken at the wrong time-point has led to unnecessary dose escalation. Checking the measurement timing during telephone follow-ups reduces this error.

In the T-Trials, men required dose adjustments in approximately 40% of cases to maintain serum testosterone in the 500 to 900 ng/dL target range, underscoring that initial dosing is a starting point, not a final prescription [2].

A Note on Testosterone, Cognition, and Mood

The T-Trials included a cognition sub-trial enrolling 493 men aged 65+ and found no significant benefit of testosterone on any cognitive domain (verbal memory, visual memory, executive function, spatial ability) after 12 months of treatment [19]. Given that cognitive decline is a major concern in men over 65, the absence of a cognitive benefit is relevant to the overall benefit-risk discussion.

Mood and energy improved modestly in some T-Trials participants, primarily those with the lowest baseline serum testosterone levels. A meta-analysis of 17 trials published in JAMA Network Open found that testosterone therapy improved self-reported energy and mood on validated scales, with the effect size being moderate (standardized mean difference 0.24 to 95% CI 0.10 to 0.38) and strongest in men with total testosterone below 230 ng/dL at baseline [20]. That translates to a real but not dramatic benefit for the men most biochemically deficient.

For men 65+ whose primary complaint is cognitive decline rather than classical hypogonadal symptoms, testosterone therapy should not be initiated as a cognitive intervention. That is not what the current evidence supports [19].