Erectile dysfunction (ED) is common, and is defined as "persistent or regular inability to achieve or maintain penis erection for satisfactory intercourse". Approximately 3% to 71% of males have this problem as they age, and it is predicted that 320 million males worldwide will have ED by 2025. However, sex remains a topic that is too sensitive for most people to discuss openly. ED therapies include oral medication, vacuum erection devices, intracavernosal injection, testosterone supplementation, surgery, and psychological counseling. In addition, germanium (Ge), titanium (Ti), and π elements are noble metals that can be used to produce far-infrared radiation. There has been little application of these metals to the treatment of ED, but their use is worth investigating. Administered as health textiles, the application of these metals are expected to promote blood circulation, especially in the reproductive system, resulting in an improved sexual performance. Hence, the researcher aimed to investigate the safety and efficacy of Ge-Ti-π elements fiber textiles as an ED treatment, assessed by using the questionnaires related to the quality of sexual function.

This clinical trial recruited 30 subjects with ED (a test group of 21 subjects and a control group of 9 subjects). Cellulosic textiles, incorporating noble metals (Ge, Ti, and π elements), developed by Green Energy Nano Technology Co., Ltd, were used in the test group, while commercially available regular textiles were used in the control group. The safety and efficacy of the treatment to the subject's sexual function quality were assessed through the International Index of Erectile Function (IIEF-5) and the validated Portuguese version of the Quality of Erection Questionnaire (QEQ) questionnaires. In the same session, the symptoms related to ED were assessed through the Premature Ejaculation Diagnostic Tool (PEDT) and the International Prostate Symptom Score (IPSS) questionnaires. The questionnaires were completed once a month and followed up for 3 months. The incidence of severe adverse effects was analyzed to assess product safety.

Inclusion Criteria:

1. The subject or legal representative has understood the contents of this experiment and has agreed to sign the participation consent form.
2. The subject is aged between 40 and 70 years.
3. The patient has a medical history of erectile dysfunction for at least three months, based on a physician's diagnosis.
4. The subject has a regular sex partner during the experimental period.

Exclusion Criteria:

1. Subject was administered oral medication (Sildenafil, Vardenafil, or Tadalafil), vacuum suction device, or corpus cavernosum injections, seven days before the experiment commenced.
2. Long-term use of antihypertensive medication (doxazosin or nitrate), antidepressants, sedatives, anti-androgens, or medications such as cimetidine for digestive ulcers.
3. Severe damage to the central nervous system (including stroke or spinal injury) within the last six months.
4. Patients with erectile dysfunction induced by non-vascular causes, such as neurological factors, hormonal factors, or related trauma.
5. Patients with vascular sclerosis.
6. Patients with psychogenic erectile dysfunction.
7. Patients who had undergone radical prostatectomy or transurethral resection of the prostate.
8. HIV patients or patients with severe liver dysfunction (GOT, GPT ≥100 IU/L).
9. Patients with genital malformations or diseases that require sexual abstinence.
10. Sex partner is pregnant or nursing.
11. Patients with Peyronie's Disease.
12. Heavy drinkers or smokers.
13. Patients with malignant tumors or prostate cancer.
14. Patients who had surgery during the study period that could affect the experimental results.
15. Subjects who had a serious clinical or mental condition that could affect the experimental procedure or evaluation.

Male