Testosterone Cypionate Erythrocytosis Alternatives: TRT Options Without Elevated Hematocrit

Which alternatives raise hematocrit less?

Head-to-head trials between formulations are rare, so the clearest comparison comes from a network meta-analysis of 29 placebo-controlled randomized trials in 3,393 men [1]. Every formulation raised mean hematocrit compared with placebo:

• Intramuscular testosterone cypionate or enanthate: 4.0% (95% CI 2.9 to 5.1)
• Gel: 3.0% (95% CI 1.8 to 4.3)
• Intramuscular testosterone undecanoate: 1.6% (95% CI 0.3 to 3.0)
• Patch: 1.4% (95% CI 0.2 to 2.6)
• Oral testosterone undecanoate: 4.3% (95% CI 0.7 to 8.0)

When the formulations were compared against each other rather than against placebo, intramuscular cypionate or enanthate rose significantly more than the patch, and the other pairs did not differ significantly [1]. Gel and injectable undecanoate were not shown to differ significantly from cypionate in this pooled analysis, and the oral form's mean rise was numerically the largest, with a wide confidence interval [1].

One retrospective review of 178 hypogonadal men treated for 3 years with a single formulation found hematocrit above 50% in 66.7% of men on injectable testosterone, 12.8% on gels and 35.1% on pellets [3]. The injection group was younger (mean 42.5 vs about 54 years) and had higher baseline hematocrit, and the study was not randomized [3]. A 2025 systematic review of drug-induced erythrocytosis found erythrocytosis rates up to 66.7% in men on prescription testosterone, with intramuscular formulations, higher doses and older age associated with higher risk [5]. Reviews of testosterone-induced erythrocytosis describe the risk as well established and note that short-acting injectable formulations have the highest incidence [6].

Blood pressure is a separate issue that applies across the class: after reviewing ambulatory blood pressure monitoring studies, FDA said the results confirmed a blood pressure increase with all testosterone products [7].

Dose and the 54% threshold

The 2025 systematic review linked higher doses, intramuscular formulations and older age to higher erythrocytosis risk [5]. The Depo-Testosterone label lists polycythemia as an adverse reaction and says to check hemoglobin and hematocrit periodically during long-term use [4]. It gives a replacement dose of 50 to 400 mg every 2 to 4 weeks [4].

A 2023 clinical consultation guide in European Urology Focus states that providers should decrease or discontinue therapy if hematocrit exceeds 54% until it normalizes [2]. The same guide says patient-specific factors should be considered when choosing the testosterone dosage and modality [2].

Clomiphene: raising the body's own testosterone

Clomiphene citrate is a selective estrogen receptor modulator used off-label for male hypogonadism [8]. It acts centrally to raise luteinizing hormone and follicle-stimulating hormone, which increases testosterone production. Unlike testosterone replacement, it does not suppress the hypothalamic-pituitary-gonadal axis, preserving intratesticular testosterone production and spermatogenesis, which is especially useful in men interested in fertility [8].

One retrospective series of 400 men treated for a mean of 25.5 months assessed treatment duration, serum testosterone, symptom improvement and side effects [9]. Among the 120 men treated for more than 3 years, 88% reached eugonadism, 77% reported improved symptoms and 8% reported side effects, most often mood changes, blurred vision and breast tenderness [9]. Estradiol rose significantly, and no significant adverse event was reported [9]. Reported adverse effects across studies include headache, dizziness, gynecomastia and exacerbation of psychiatric illness [8].

When hematocrit stays high

The 2025 systematic review found no clear consensus among clinicians on how to diagnose and manage drug-induced erythrocytosis [5]. A 2025 hematology review of JAK2 wild-type erythrocytosis says there are no evidence-based treatment guidelines, and that low-dose aspirin and/or phlebotomy might be considered on an individualized basis when there are hyperviscosity symptoms, cardiovascular comorbidities or a history of thrombosis [10]. That review is not specific to testosterone.

Testosterone is only one cause of acquired erythrocytosis. Others include cardiopulmonary disease, altitude, renal artery stenosis and erythropoietin-secreting tumors, and polycythemia vera is excluded with JAK2 mutation screening [10].

The Endocrine Society guideline recommends against starting testosterone therapy in men with elevated hematocrit and recommends monitoring hematocrit during the first year of treatment [11].