Table 3 Characteristics and results of the studies analyzed

Olsen et al. (2014) [24] 

Age between 18 and 80 years old. Diagnosis of ED of more than 6 months of evolution. Maintenance of stable sexual partner of at least 3 months of evolution. Erection Hardness Scale score of less than 2 points. International Index of Erectile Function score of less than 20 points

Diagnosis of psychogenic ED, neurological and/or cardiac pathology that prevents sexual intercourse. History of prostatectomy, rectal removal, pelvic radiotherapy and/or cancer in the previous five years. Treatment with antiandrogens

Improved erection quality

No improvement in erection function

Yee et al. (2014) [33] 

Age over 18 years old. Diagnosis of ED of more than 6 months of evolution. Maintenance of a heterosexual couple of at least 6 months. Men's Sexual Health Inventory score lower than 21 points

Diagnosis of non-vascular

endocrine, neurological, pharmacological or penile deformities. History of pelvic surgery and/or pelvic radiotherapy treatment. Presence of penile implant

Improvement of erectile function in patients with severe ED

No improvement in erection quality

Kitrey et al. (2016) [32] 

Initial positive response to PDEI-5 and termination of treatment due to lack of efficacy in the last year. Erection Hardness Scale score of at least 2 points

Presence of penile malformations and/or unstable medical situation. Diagnosis of neurological and/or hormonal pathologies. History of prostate cancer

Improvement of erectile function, erection quality, penile hemodynamics

Fojecki et al. (2017) [26] 

Age over 40 years old. Diagnosis of ED of more than 6 months of evolution. Maintenance of stable relationship of at least 3 months

History of surgery, pelvic radiotherapy and/or use of penile prosthesis. Treatment with anticoagulants and/or antiandrogens. Presence of penile deformities, and/or testosterone levels below 8 nmol/dL. Diagnosis of severe cardiac and/or pulmonary pathologies and/or neurological and/or psychiatric disorders. International Index of Erectile Function score higher than 25 points. Existence of pregnant partner

Improvement of quality of sexual life

No improvement in erectile function and erection quality

Qi et al. (2017) [35] 

Age between 20 and 55 years old. Diagnosis of ED according to the European and Chinese ED Guidelines. Presence of abnormal penile tumescence and rigidity. International Index of Erectile Function score less than 22 points

History of prostate surgery, trauma and/or cancer in the previous 5 years. Diagnosis of Diabetes Mellitus, arterial hypertension, spinal cord injury, psychiatric pathology and/or hematological diseases with clinical manifestations. Presence of penile deformities. Consumption of androgens or antiandrogens. History of previous treatment with medication, vacuum erection devices, intracavitary cavernous injection and/or intraurethral pharmacotherapy

Improved erectile function, sexual satisfaction, erection quality and ability to maintain sexual intercourse

Sramkova et al. (2017) [27] 

Diagnosis of ED of less than 6 months of evolution. Maintenance of stable partner and regular sexual activity with, at least, two relations per week

History of pelvic surgery. Diagnosis of psychogenic or neurological ED and/or neurological pathology

Improvement of erectile function, erection quality, ability to maintain sexual intercourse and sexual satisfaction of the patient and partner

Kalyvianakis et al. (2018) [34] 

Cavernous artery peak systolic velocity less than 35 cm/s. International Index of Erectile Function score less than 26 points

Diagnosis of psychiatric pathologies, psychogenic or neurological ED, active cancer, untreated endocrine diseases, uncontrolled Diabetes Mellitus, arterial hypertension, cardiovascular pathology and/or hemophilia. Previous treatment with PDEI-5. Presence of penile deformities and/or high risk of thrombosis. History of penile and/or pelvic surgery

Improvement of erectile function, sexual satisfaction, penile hemodynamics

Zewin et al. (2018) [37] 

Diagnosis of bladder cancer with muscle invasion. Presence of sexual motivation. Maintenance of stable relationship of more than 6 months of antiquity. Sexually active men without erectogenic aids before the cancer intervention

Diagnosis of Peyronie's disorder, Diabetes Mellitus and/or psychiatric disorders. Presence of inflammation in the area of application and/or postoperative complications

Improvement of erectile function, erection quality and hemodynamics of the cavernous arteries

Baccaglini et al. (2019) [36] 

Age over 75 years old. Maintenance of a heterosexual relationship of at least 3 months. History of prostatectomy with nerve preservation. International Index of Erectile Function score less than 18 points

Previous treatment with pelvic radiotherapy and/or antiandrogens. Diagnosis of psychiatric pathologies, hypogonadism and/or uncontrolled diabetes mellitus. Presence of postoperative complications

Improvement of erectile function and urinary continence

Vinay (2019) [28] 

Age over 18 years old. Diagnosis of ED of vascular origin without response to PDEI-5 of between 6 months and 7 years of evolution. International Index of Erectile Function score lower than 26 points

History of treatment with PDEI-5 and/or pelvic radiotherapy and/or cancer in the year prior to the study. Diagnosis of non-vascular ED and/or acute or chronic disease. Treatment with psychotropic drugs. Presence of penile deformities and/or a value greater than 3 on the International Normalized Ratio

Improvement of erectile function, erection quality, sexual satisfaction and ability to maintain sexual intercourse

Kim et al. (2020) [31] 

Age over 20 years old. Diagnosis of medium or moderate ED of at least 6 months of evolution. Maintenance of stable sexual relationship for more than 3 months

Diagnosis of severe and/or psychogenic ED, neurological and/or cardiac pathologies that inhibit sexual contact. History of prostatectomy, rectal excision and/or pelvic radiotherapy. Presence of anatomical malformations. Treatment with anticoagulants

Improvement of erectile function, erection quality and sexual satisfaction

Geyik (2021) [23] 

Patients who used 5 mg daily of PDEI-5 and still could not achieve a penile erection that would allow satisfactory sexual intercourse

Glycosylated hemoglobin levels > 7 ng/ml. Hypogonadism. Cardiac and antihypertensive medications not adjusted in consultation. History of pelvic surgery. History of degenerative neurological disorders. Lack of information

Significant improvements in sexual function in both groups. Improvements in intravaginal ejaculation latency time in Group 2

Ortac et al. (2021) [29] 

Age between 18 and 74 years. Diagnosis of mild ED and confirmed with Doppler ultrasound (International Index of Erectile Function score = 17–25)

Uncontrolled diabetes. Testosterone deficiency. Erection drugs during the first 4 weeks of study. Previous treatment with PDEI-5. History of concomitant neurological, hematological, cardiovascular disease or cancer

Improvement of erectile function

Shendy et al. (2021) [25] 

Age over 18 years old. Body Mass Index less than 30 kg/m². Diagnosis of controlled type II diabetes mellitus and medium or moderate ED of at least 6 months of evolution

History of pelvic surgery. Diagnosis of chronic psychiatric, neurological and/or hematological pathologies. Presence of penile deformities. Non-response to PDEI-5 and/or consumption in the month prior to the study

Improved erectile function and penile hemodynamics

Motil et al. (2022) [30] 

Patients after surgery who did not have ED preoperatively and suffered mild-severe postoperative ED

Previous surgery or radiotherapy to the pelvic region. Anatomical abnormalities of the penis. Chronic hematologic disease. Oral or injectable anti-androgens. Cardiovascular conditions that impede sexual function

Improvement of erectile function