Monitoring testosterone replacement therapy with transdermal gel: when and how?

PURPOSE

Testosterone replacement therapy (TRT) is recommended for the treatment of most cases of male hypogonadism. Transdermal testosterone (T) gels are commonly used in clinical practice; however, there is little evidence concerning how to monitor dosage to bring and maintain serum T levels in the normal physiologic range.

METHODS

We examined 30 hypogonadal patients undergoing treatment with 40 mg/day transdermal 2% testosterone gel. After a week from treatment onset, all patients underwent a total of four measurements to assess serum total T, bioavailable T and free T at + 2 h (samples A and A') and + 23 h (samples B and B').

RESULTS

No significant difference was found concerning total, free and bioavailable T between the two samples taken at the same time points (A vs A' and B vs B'). A repeated-measures mixed effects regression model showed significantly lower serum levels of total, free and bioavailable T at + 23 h compared to + 2 h (total T, β = - 3.050 ± 0.704, p < 0.001; free T, β = - 85.187 ± 22.746, p < 0.001; bioavailable T, β = - 1.519 ± 0.497, p = 0.003) without a significant between-sample variability. Serum T > 3.5 ng/ml at + 2 h was reached in 21/30 patients (70%), but only 11 (36.7%) still had adequate serum T at + 23 h.

CONCLUSION

Assessment of TRT with transdermal gels at its peak and at its minimum could be useful in providing a finely tailored treatment for hypogonadal men, both preventing supra-physiological levels and maintaining adequate concentrations through the day.

Psychopathology of first-episode psychosis in HIV-positive persons in comparison to first-episode schizophrenia: a neglected issue

This study aims to detect different psychopathological dimensions in first-episode psychoses with different underlying causes. We evaluated 22 subjects with first-episode psychosis, who differed in biological variables (HIV-positive versus HIV-negative) and who were compared by using the Structured Clinical Interview for DSM-III-Reviewer, the 18-item Brief Psychiatric Rating Scale (BPRS), the 17-item Hamilton Depression Rating Scale, the 14-item Hamilton Anxiety Rating Scale and the Mini-Mental State Examination. HIV-positive subjects had higher mean scores on the global BPRS and on the paranoid Positive and Negative Syndrome Scale subscale compared with HIV-negative subjects. Conversely, higher prevalence of affective and anxious symptoms was found in the HIV-negative patients in comparison to HIV-positives. HIV-positives had significantly greater attention/concentration impairment than HIV-negative persons. In conclusion, taking into account psychopathological dimensions may help psychiatrists in clinical decision-making regarding the differential diagnosis of psychotic symptoms. The psychopathological pattern of first-episode psychosis in HIV-positive patients may represent an 'elementary model' of acute psychosis characterized by paranoid delusions in the absence of the usual affective symptoms.

Changes in residual volume during induced bronchoconstriction in healthy and asthmatic subjects

The increase of residual volume (RV) was investigated during acute bronchoconstriction induced in healthy subjects by methacholine (MCh) (Group 1, n = 13) and in asthmatics by MCh (Group 2, n = 21), or housemite dust (Group 3, n = 11) during early and late airway responses (EAR and LAR), or a series of deep breaths (Group 4, n = 7). In all subjects the difference between residual volume after partial (RVp) and maximal maneuver (RV), expressed as a percentage of control FVC, increased during bronchoconstriction and was correlated with the percent increase of maximal to partial flow ratio at 50% of control FVC (M/P50) (r = 0.854, p < 0.0001). At comparable reduction of partial expiratory flow at 50% of control FVC (VP50), the decreases of FEV1 and FVC were less in healthy than asthmatic subjects, whereas the change of FEV1/FVC was similar in all groups, reflecting similar change in slope of flow-volume curves. The increase of RVp was similar in all groups (range: 15 to 19%), but the increase of RV was 6 +/- 1% (SEM) in healthy subjects and significantly greater (range: 11.1 to 13.3%) in all groups of asthmatics (p < 0.02, analysis of variance [ANOVA]). The effect of deep inhalation (DI) on the airway caliber as assessed by the increase of M/P50 was higher in normal subjects than in all groups of asthmatics (p < 0.0001). A negative correlation was found between the increases of RV and M/P50 in all groups (r = -0.358, p < 0.01), suggesting that healthy subjects had a limited increase of RV because of a marked bronchodilator effect of DI.(ABSTRACT TRUNCATED AT 250 WORDS)

Failure of aminophylline and salbutamol to improve respiratory muscle function and exercise tolerance in healthy humans

We investigated the effects of intravenously administered aminophylline (A; 6 mg/kg over 20 min, followed by 0.9 mg/kg/h), salbutamol (S; 4 micrograms/kg over 20 min, followed by 3 micrograms/kg/h) and placebo (P; saline solution) on the strength of the respiratory muscles, the ventilatory endurance and the exercise tolerance in 7 healthy humans. Neither A nor S caused bronchodilation, as shown by the lack of change in FEV1. The strength of respiratory muscles, as measured by maximal inspiratory pressure (MIP), and the ventilatory endurance, as measured by sustainable inspiratory pressure (SIP), were not statistically different after A (MIP: 136.5 +/- SE 11.6 cm H2O; SIP: 104.2 +/- 8.4 cm H2O or after S (MIP: 135.7 +/- 11.5; SIP: 107.1 +/- 10.4) compared to after P (MIP: 127.1 +/- 10.1; SIP: 105.0 +/- 5.9). Significant changes in 12-min walking distance, perceived exertion rate, anaerobic threshold, maximal work output, maximal O2 uptake were observed neither after A nor after S. The exchange ratio and heart rate were higher after A and S than after P at some steps of a progressive, symptom-limited, treadmill-based exercise test. This might be the result of metabolic or cardiovascular adaptations elicited by these drugs. We conclude that A or S at therapeutic concentrations have no clinically relevant beneficial effects on ventilatory muscle function and exercise tolerance in healthy subjects.

Anti-inflammatory agents: determination of ibuproxam and its metabolite humans. Correlation between bioavailability, tolerance and chemico-physical characteristics

A study on absorption and elimination in the urine of 2-(4-isobutylphenyl)-propiohydroxamic acid (ibuproxam, Ibudros) (400 mg film tablets) after administration to healthy volunteers is reported. In the plasma, only a minimum concentration of ibuproxam as such could be found: instead its chief metabolite ibuprofen mainly present, with top peaks at 45 min. The maximum ibuprofen concentration in the plasma--when obtained through metabolization of ibuproxam--is significantly higher than after administration of an equal dose of ibuprofen. This phenomenon is related to the chemico-physical characteristics of the two compounds.

[Some new derivatives of aromatic oximes with beta-blocking activity]

Because of the great importance assumed by beta-blocking agents in recent years, some new derivatives of aromatic oxime ethers, in the syn form, have been synthesized, having the following general structure: The above compounds were obtained by two different methods designed to demonstrate their structure. The results of some pharmacological tests are also reported, in order to give an indication of the real activity of the new compounds synthesized.