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result(s) for
"Libido"
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Direct comparison of the acute subjective, emotional, autonomic, and endocrine effects of MDMA, methylphenidate, and modafinil in healthy subjects
by
Liechti, Matthias E.
,
Dolder, Patrick C.
,
Schmid, Yasmin
in
Acute effects
,
Adult
,
Adverse drug reactions
2018
Rationale
3,4-Methylenedioxymethamphetamine (MDMA) is used recreationally and investigated as an adjunct to psychotherapy. Methylphenidate and modafinil are psychostimulants that are used to treat attention-deficit/hyperactivity disorder and narcolepsy, respectively, but they are also misused as cognitive enhancers. Little is known about differences in the acute effects of equally cardiostimulant doses of these stimulant-type substances compared directly within the same subjects.
Methods
We investigated the acute autonomic, subjective, endocrine, and emotional effects of single doses of MDMA (125 mg), methylphenidate (60 mg), modafinil (600 mg), and placebo in a double-blind, cross-over study in 24 healthy participants. Acute drug effects were tested using psychometric scales, the Facial Emotion Recognition Task (FERT), and the Sexual Arousal and Desire Inventory (SADI).
Results
All active drugs produced comparable hemodynamic and adverse effects. MDMA produced greater increases in pupil dilation, subjective good drug effects, drug liking, happiness, trust, well-being, and alterations in consciousness than methylphenidate or modafinil. Only MDMA reduced subjective anxiety and impaired fear recognition and led to misclassifications of emotions as happy on the FERT. On the SADI, only MDMA produced sexual arousal-like effects. Only MDMA produced marked increases in cortisol, prolactin, and oxytocin. In contrast to MDMA, methylphenidate increased subjective anxiety, and methylphenidate and modafinil increased misclassifications of emotions as angry on the FERT. Modafinil had no significant subjective drug effects but significant sympathomimetic and adverse effects.
Conclusions
MDMA induced subjective, emotional, sexual, and endocrine effects that were clearly distinct from those of methylphenidate and modafinil at the doses used.
Journal Article
Effects of Testosterone Treatment in Older Men
by
Bhasin, Shalender
,
Ensrud, Kristine E
,
Farrar, John T
in
Aged
,
Chronic illnesses
,
Depression - drug therapy
2016
In this study, men 65 years of age or older with low serum testosterone and symptoms of hypoandrogenism received testosterone or placebo for a year. Testosterone had a moderate benefit in sexual function and some benefit in mood but no benefit in vitality or walking distance.
Testosterone concentrations in men decrease with increasing age.
1
,
2
Many symptoms and conditions similar to those that are caused by low testosterone levels in men with pituitary or testicular disease become more common with increasing age. Such symptoms include decreases in mobility, sexual function, and energy. These parallels suggest that the lower testosterone levels in older men may contribute to these conditions.
Previous trials of testosterone treatment in men 65 years of age or older, however, have yielded equivocal results. Although testosterone treatment consistently increased muscle mass and decreased fat mass,
3
,
4
effects on physical performance,
3
,
5
,
6
sexual function, . . .
Journal Article
Cocaine administration dose-dependently increases sexual desire and decreases condom use likelihood: The role of delay and probability discounting in connecting cocaine with HIV
by
Johnson, Matthew W.
,
Sweeney, Mary M.
,
Herrmann, Evan S.
in
Adult
,
Analysis
,
Biomedical and Life Sciences
2017
Objectives
Although cocaine use has been linked to sexual HIV risk behavior for decades, the direct effects of cocaine on sexual desire and sexual decision-making are unexamined. Research suggests delay discounting (devaluation of future outcomes) and probability discounting (devaluation of uncertain outcomes) play roles in condom use decisions. This study examined the effect of cocaine administration on sexual desire, hypothetical condom use, and discounting tasks.
Methods
This double-blind, within-subjects study compared the effects of 0, 125, and 250 mg/70 kg oral cocaine HCl in 12 cocaine users. Measures included sexual desire and other subjective ratings, the Sexual Delay Discounting Task, the Sexual Probability Discounting Task, and monetary delay and probability discounting tasks.
Results
Cocaine caused dose-related increases in sexual desire and prototypical stimulant abuse-liability ratings. Relative to placebo, cocaine did not significantly alter condom use likelihood when condoms were immediately available or when sex was associated with 100% certainty of sexually transmitted infection (STI). In contrast, cocaine dose-dependently strengthened the effect of delay (sexual delay discounting) and STI uncertainty (sexual probability discounting) in decreasing condom use likelihood. Cocaine caused no significant change in monetary delay and probability discounting.
Conclusion
This is the first study showing that cocaine administration increases sexual desire. Detrimental effects of cocaine on sexual risk were only observed when safer sex required delay, or STI risk was uncertain (representative of many real-world scenarios), suggesting a critical role of discounting processes. Lack of monetary effects highlights the importance of studying clinically relevant outcomes when examining drug effects on behavioral processes.
Journal Article
Dose-Response Relationships Between Gonadal Steroids and Bone, Body Composition, and Sexual Function in Aging Men
by
Taylor, Alexander P
,
Leder, Benjamin Z
,
Lee, Hang
in
Acetates
,
Adiposity - drug effects
,
Adiposity - physiology
2020
Abstract
Context
Most labs set the lower limit of normal for testosterone at the 2.5th percentile of values in young or age-matched men, an approach that does not consider the physiologic changes associated with various testosterone concentrations.
Objective
To characterize the dose-response relationships between gonadal steroid concentrations and measures regulated by gonadal steroids in older men.
Design, Participants, and Intervention
177 men aged 60 to 80 were randomly assigned to receive goserelin acetate plus either 0 (placebo), 1.25, 2.5, 5, or 10 grams of a 1% testosterone gel daily for 16 weeks or placebos for both medications (controls).
Primary Outcomes
Changes in serum C-telopeptide (CTX), total body fat by dual energy X-ray absorptiometry, and self-reported sexual desire.
Results
Clear relationships between the testosterone dosage (or the resulting testosterone levels) and a variety of outcome measures were observed. Changes in serum CTX exceeded changes in the controls in men whose testosterone levels were 0 to 99, 100 to 199, 200 to 299, or 300 to 499 ng/dL, whereas increases in total body fat, subcutaneous fat, and thigh fat exceeded controls when testosterone levels were 0 to 99 or 100 to 199 ng/dL. Sexual desire and erectile function were indistinguishable from controls until testosterone levels were <100 ng/dL.
Conclusion
Changes in measures of bone resorption, body fat, and sexual function begin at a variety of testosterone concentrations with many outcome measures remaining stable until testosterone levels are well below the stated normal ranges. In light of this variation, novel approaches for establishing the normal range for testosterone are needed.
Journal Article
Gonadal Steroids and Body Composition, Strength, and Sexual Function in Men
by
Leder, Benjamin Z
,
Thomas, Bijoy J
,
Pallais, J. Carl
in
17β-Estradiol
,
Acetic acid
,
Adipose Tissue
2013
This study, designed to determine the relative degree of testosterone deficiency, estradiol deficiency, or both at which undesirable bodily changes occur, showed that some features of male hypogonadism are due to both androgen deficiency and estrogen deficiency.
Testosterone therapy is prescribed for millions of men each year, and the number is increasing rapidly. Prescription sales of testosterone increased by 500% in the United States between 1993 and 2000.
1
Most testosterone prescriptions are written to treat nonspecific symptoms, such as fatigue or sexual dysfunction, when accompanied by testosterone levels below the laboratory reference range. Currently, testosterone levels that are at least 2 SD below the mean value for healthy young adults are classified as low.
1
,
2
Although convenient, this classification fails to consider the physiological consequences of specific testosterone levels.
More than 80% of circulating estradiol in men . . .
Journal Article
Effect of Testosterone Replacement Therapy on Sexual Function and Hypogonadal Symptoms in Men with Hypogonadism
by
Pencina, Karol M
,
Cunningham, Glenn R
,
Wannemuehler, Kathleen
in
Aged
,
Cardiovascular diseases
,
Cardiovascular Diseases - etiology
2024
Abstract
Context
Few long-term randomized trials have evaluated the efficacy of testosterone replacement therapy (TRT) in improving sexual function and hypogonadal symptoms in men with hypogonadism and whether effects are sustained beyond 12 months.
Objective
The Testosterone Replacement therapy for Assessment of long-term Vascular Events and efficacy ResponSE in hypogonadal men (TRAVERSE) study evaluated the effect of TRT on major adverse cardiovascular events in middle-aged and older men with hypogonadism. The Sexual Function Study, nested within the parent trial, determined testosterone's efficacy in improving sexual activity, hypogonadal symptoms, libido, and erectile function among men reporting low libido.
Methods
Among 5204 men, 45-80 years, with 2 testosterone concentrations <300 ng/dL, hypogonadal symptoms, and cardiovascular disease (CVD) or increased CVD risk enrolled in the TRAVERSE trial, 1161 with low libido were enrolled in the Sexual Function Study (587 randomized to receive 1.62% testosterone gel and 574 to placebo gel for the duration of their participation in the study). Primary outcome was change from baseline in sexual activity score. Secondary outcomes included hypogonadal symptoms, erectile function, and sexual desire.
Results
TRT was associated with significantly greater improvement in sexual activity than placebo (estimated mean [95% CI] between-group difference 0.49 [0.19,0.79] and 0.47 [0.11, 0.83] acts per day at 6 and 12 months, respectively; omnibus test P = .011); treatment effect was maintained at 24 months. TRT improved hypogonadal symptoms and sexual desire, but not erectile function, compared with placebo.
Conclusion
In middle-aged and older men with hypogonadism and low libido, TRT for 2 years improved sexual activity, hypogonadal symptoms, and sexual desire, but not erectile function.
Journal Article
Low Energy Availability in Athletes 2020: An Updated Narrative Review of Prevalence, Risk, Within-Day Energy Balance, Knowledge, and Impact on Sports Performance
2020
Low energy availability (EA) underpins the female and male athlete triad and relative energy deficiency in sport (RED-S). The condition arises when insufficient calories are consumed to support exercise energy expenditure, resulting in compromised physiological processes, such as menstrual irregularities in active females. The health concerns associated with longstanding low EA include menstrual/libido, gastrointestinal and cardiovascular dysfunction and compromised bone health, all of which can contribute to impaired sporting performance. This narrative review provides an update of our previous review on the prevalence and risk of low EA, within-day energy deficiency, and the potential impact of low EA on performance. The methods to assess EA remain a challenge and contribute to the methodological difficulties in identifying “true” low EA. Screening female athletic groups using a validated screening tool such as the Low Energy Availability in Females Questionnaire (LEAF-Q) has shown promise in identifying endurance athletes at risk of low EA. Knowledge of RED-S and its potential implications for performance is low among coaches and athletes alike. Development of sport and gender-specific screening tools to identify adolescent and senior athletes in different sports at risk of RED-S is warranted. Education initiatives are required to raise awareness among coaches and athletes of the importance of appropriate dietary strategies to ensure that sufficient calories are consumed to support training.
Journal Article
Hypoactive Sexual Desire Disorder: International Society for the Study of Women's Sexual Health (ISSWSH) Expert Consensus Panel Review
2017
The objective of the International Society for the Study of Women's Sexual Health expert consensus panel was to develop a concise, clinically relevant, evidence-based review of the epidemiology, physiology, pathogenesis, diagnosis, and treatment of hypoactive sexual desire disorder (HSDD), a sexual dysfunction affecting approximately 10% of adult women. Etiologic factors include conditions or drugs that decrease brain dopamine, melanocortin, oxytocin, and norepinephrine levels and augment brain serotonin, endocannabinoid, prolactin, and opioid levels. Symptoms include lack or loss of motivation to participate in sexual activity due to absent or decreased spontaneous desire, sexual desire in response to erotic cues or stimulation, or ability to maintain desire or interest through sexual activity for at least 6 months, with accompanying distress. Treatment follows a biopsychosocial model and is guided by history and assessment of symptoms. Sex therapy has been the standard treatment, although there is a paucity of studies assessing efficacy, except for mindfulness-based cognitive behavior therapy. Bupropion and buspirone may be considered off-label treatments for HSDD, despite limited safety and efficacy data. Menopausal women with HSDD may benefit from off-label testosterone treatment, as evidenced by multiple clinical trials reporting some efficacy and short-term safety. Currently, flibanserin is the only Food and Drug Administration-approved medication to treat premenopausal women with generalized acquired HSDD. Based on existing data, we hypothesize that all these therapies alter central inhibitory and excitatory pathways. In conclusion, HSDD significantly affects quality of life in women and can effectively be managed by health care providers with appropriate assessments and individualized treatments.
Journal Article
The Heteronormativity Theory of Low Sexual Desire in Women Partnered with Men
by
Brotto, Lori A.
,
Herbenick, Debby
,
van Anders, Sari M.
in
Anatomical systems
,
Behavioral Science and Psychology
,
Causality
2022
Low sexual desire in women partnered with men is typically presumed to be a problem—one that exists in women and encourages a research agenda on causation and treatment targeting women. In this paper, we present a distinct way forward for research on low sexual desire in women partnered with men that attends to a more structural explanation: heteronormativity. A heteronormative worldview assumes that relationships and structures are heterosexual, gender (usually conflated with sex) is binary and complementary, and gender roles fit within narrow bounds including nurturant labor for women. We propose the heteronormativity theory of low sexual desire in women partnered with men, arguing that heteronormative gender inequities are contributing factors. We outline four hypotheses and their predictions related to: inequitable divisions of household labor, blurring of partner and mother roles, objectification of women, and gender norms surrounding sexual initiation. We discuss some mechanisms—social, physiological, and otherwise—for the heteronormativity theory, especially related to stress, objectification, and nurturance. We close by noting some limitations of our paper and the ways that the heteronormativity theory of low sexual desire in women partnered with men provides a rigorous, generative, and empirical way forward.
Journal Article
Distinct Clusters of Testosterone Levels, Symptoms, and Serum Trace Elements in Young Men: A Cross-Sectional Analysis
2025
Background/Objectives: Modern societal stressors have been linked to declining testosterone levels among young men, contributing to somatic, psychological, and sexual health problems. Despite growing evidence suggesting a link between trace elements and testosterone-related symptoms, there are only a few comprehensive analyses on younger populations. This study’s aim was to examine how serum trace elements modulate the relationship between testosterone levels and symptom severity. Methods: This cross-sectional study included 225 young men seeking infertility consultation in Japan. Serum total and free testosterone levels were measured, along with self-reported symptoms using the Aging Males’ Symptoms scale (somatic, psychological, sexual) and the Erection Hardness Score. The serum concentrations of 20 trace elements were measured. We used unsupervised clustering to classify participants based on testosterone levels and symptom severity and then compared the distribution of trace elements among the resulting clusters. Results: Three distinct clusters emerged: (1) lowest testosterone with highest symptom severity, (2) intermediate, and (3) highest testosterone with minimal symptoms. Interestingly, the intermediate cluster displayed low testosterone levels but minimal symptoms. Eleven trace elements (phosphorus, sulfur, potassium, calcium, iron, zinc, arsenic, rubidium, strontium, molybdenum, and cesium) were identified as potential contributors to testosterone dynamics. Weighted quantile sum regression indicated that phosphorus, strontium, and molybdenum negatively influenced testosterone outcomes, whereas iron, sulfur, and zinc were beneficial. Conclusions: Serum trace element profiles are significantly associated with testosterone levels and symptom severity in young men. Targeted interventions may address testosterone decline and its implications. These findings may help develop tailored strategies for optimizing male health.
Journal Article