We thank Felix Dörflinger and Maximilian Kathofer for their dedicated assistance with data collection. Future research will also be required to more systematically test whether testosterone’s influence on the prosocial audience effect is sensitive to the gender, number, and salience of the present observers. Further research is, however, needed to determine whether testosterone reduces lying per se, or only in situations where dishonest behavior may be considered "cheap", dishonorable, and lower the subject’s feelings of pride and self-image . Our results are, furthermore, in line with studies showing that testosterone decreases deception 55,56,57. For these reasons, we suggest future studies of how testosterone affects status-seeking behavior should focus on exploring these cultural differences, specifically by including measures of value orientations, self-construal, implicit behavioral tasks, as well as assessments of dopamine receptor polymorphisms. Thus, these findings are suggestive of the interpretation that by inducing a non-confirming attitude, testosterone reaches its principle goal - to be observed as having high status and competence 17, 46. To examine this topic further, studies on testosterone and audience effect should include more explicit measures of subjectively perceived stress and anxiety. Pharmacokinetic studies confirm that daily dosing achieves more steady-state testosterone levels compared to weekly or bi-weekly protocols, but the clinical significance varies per individual. Daily injections maintain near steady-state hormone levels, reducing mood swings and erythrocytosis risk but require more frequent administration. The median dose of SC testosterone in this study (75 mg/week) and in previous studies 13–16 is less than the commonly recommended dose of 100 mg/week for IM dosing 1, 4. Larger studies could be undertaken to obtain more detailed information regarding variability of serum concentrations or differences in serum levels following injections at different sites, or possible effects of different BMIs. The slight decline in mean serum testosterone levels just prior to an injection was not accompanied by a decline in subjective symptoms of energy or mood and is thus unlikely to have clinical significance. Data are shown as mean serum total testosterone among measurements taken between testosterone injections. Most recent serum testosterone measurement while on therapy and prior to the study week (performed at LabCorp). Most specialists instead aim for very low transdermal dosing that yields mid-female reference levels and minimizes virilizing effects, with reassessment after 6–12 weeks and periodic monitoring thereafter (lipids, LFTs, hematocrit where appropriate). But 200 mg/week exceeds the typical replacement range for many patients and raises safety considerations (hematocrit, blood pressure, lipids, acne, edema). For example, a clinic might list cypionate/enanthate at 75–150 mg/week (weekly or split into two injections), then provide an adjustment ladder in 10–20 mg steps based on follow-up labs and symptoms. These fluctuations are quantifiable through pharmacokinetic analyses demonstrating greater area under the curve (AUC) stability with more frequent dosing. The relatively low injection frequency can lead to pronounced hormonal fluctuations, causing transient supraphysiological peaks followed by suboptimal troughs. Timing considerations emphasize injecting every 14 days to balance efficacy and patient convenience, minimizing peaks and troughs inherent to longer intervals. These hormonal variances can influence both efficacy and the incidence of side effects, necessitating careful monitoring. Moreover, this protocol supports steady-state pharmacokinetics, which may reduce side effects linked to supraphysiological peaks. Additionally, the requirement for daily subcutaneous or intramuscular administration may affect treatment adherence. Evidence suggests daily injection benefits include improved mood stability, reduced erythrocytosis risk, and more consistent androgen receptor activation. A pharmacology overview explaining how ester length affects blood levels is available in this peer-reviewed review (PMC). You can see the labeled ranges in the Drugs.com dosage monograph, while monitoring/titration principles are detailed in the Endocrine Society guideline. Many groups intervene when hematocrit approaches about 54%—for example, the AUA Testosterone Deficiency Guideline and a contemporary clinical review both describe this threshold and suggested actions (dose reduction, temporary hold, or phlebotomy where appropriate). After a dose change, follow-up commonly occurs at 3–6 months, then periodically once stable. Interpreting numbers in context helps your clinician adjust your trt dosage based on both labs and symptoms rather than chasing a single target. In simple terms, it replaces the testosterone your body is not producing in sufficient amounts, aiming to relieve symptoms like low energy, decreased libido, or reduced muscle mass. TRT is a doctor-prescribed treatment for confirmed low testosterone (hypogonadism). We’ll cover typical formulations (like cypionate and enanthate), dosing frequencies, how to read mg-to-mL conversions, and what lab numbers matter. To provide context for this pharmacokinetic study, we included the clinical efficacy and safety data for the patients in this report. These patients were also included in a larger longer-term evaluation of clinical safety and efficacy of SC testosterone administration . The normal adult male range for total testosterone was 250 to 1100 ng/dL and for free testosterone was 46 to 224 pg/mL. Self-injection by patients with their own materials allowed for a real-life situation for our study. If patients missed a scheduled blood draw, they continued with the remainder of scheduled blood draws for the week, continued their Monday dosing schedule, and made up the missed blood draw on the same day in the following week at the originally scheduled time frame. One hour and 50 min after the gel application, participants provided a second saliva sample and subsequently began the experimental task (see Fig. 1). The only difference between the testosterone and placebo gel was that the placebo gel did not contain testosterone. 20 min after arrival, participants were asked to drool 2 mL of saliva into a polyethylene collection tube. Testing took place in groups of three to five participants, who were seated individually in small cubicles within the same testing room. No side-effects or adverse events were reported during or after the experimental sessions. All participants gave written consent and received a financial reward for their participation consisting of a flat fee and a bonus based on their task performance. In the applied linear mixed models, our sample size gave us 90% power to detect three-way and 86% power to detect 4-way interaction effects of size f ≥ 0.15.
