Safety And Efficacy Of L-Arginine Monotherapy Versus Tadalafil Monotherapy Versus Their Combination In Men With Erectile Dysfunction; A Prospective Randomized Study

Introduction Sexual dysfunctions are annoying health problems with the erectile problems forming the main part of them. Erectile dysfunction (ED) is defined as the persistent inability to obtain or maintain an erection that is sufficient to allow satisfactory sexual intercourse.[1] Aim of Work To evaluate the role of L-arginine monotherapy versus Tadalafil monotherapy versus their combination for the treatment of erectile dysfunction .

Patients and methods:

Inclusion criteria:

• Naive ( not previously treated) male patient with mild to moderate ED according to SHIM Questionnaire.

Exclusion criteria:

• Kidney disease or liver failure
• Coronary heart disease
• Peyronie's disease
• Neurological disease that may related to ED

Study Overview

• Status: Completed
• Conditions: Erectile Dysfunctions
• Intervention / Treatment: Drug: L-Arginine; Drug: Tadalafil 5 mg

Detailed Description

Safety And Efficacy Of L-Arginine Monotherapy Versus Tadalafil Monotherapy Versus Their Combination In Men With Erectile Dysfunction; A Prospective Randomized Study

Introduction Sexual dysfunctions are annoying health problems with the erectile problems forming the main part of them. Erectile dysfunction (ED) is defined as the persistent inability to obtain or maintain an erection that is sufficient to allow satisfactory sexual intercourse.[1] It is difficult to obtain accurate values for the true prevalence of erectile dysfunction, as many patients fail to seek any medical attention The best available data according to the Massachusetts Male Aging Study indicates that 52% of males between 40 and 70 years of age are affected with erectile problems, and about 70% of males are having some subjective issues with erections at the age of 70 years.[2] Erection is a neurovascular event in which a key mediator is nitric oxide (NO). It has been shown that there is reduced NO bioactivity in ED.[3] Oral phosphodiesterase-5 inhibitors (PDE-5 inhibitors), such as sildenafil and Tadalafil, are usually the first-line treatment of erectile dysfunction. They are effective in a wide range of etiologies including cardiovascular disease, diabetes, and hypogonadism. They act by decreasing the degradation of cyclic GMP via phosphodiesterase inhibition, which increases the relaxation of cavernosal smooth muscle and cavernosal arterial blood flow. It is important to note that PDE-5 inhibitors do not initiate the erectile response. Sexual stimulation is required to release nitric oxide from the vascular endothelium and penile nerve endings to commence the erectile process. PDE-5 inhibitors are highly effective and have an overall success rate of up to 76%.[4]

As L-arginine is a natural precursor of NO and its good availability is understood to have positive effect on NO production. Data regarding the pattern of use of L-arginine for sexual problems, which is considered one of the more widely used alternatives or adjuncts to regular drugs used in the patients of ED.[5] Aim of Work To evaluate the role of L-arginine monotherapy versus Tadalafil monotherapy versus their combination for the treatment of erectile dysfunction .

Patients and methods This clinical prospective study will be carried out on patients attending urology clinic in Fayoum University Hospital with ED

Sample size :

Inclusion criteria:

• Naive ( not previously treated) male patient with mild to moderate ED according to SHIM Questionnaire.

Exclusion criteria:

• Kidney disease or liver failure
• Coronary heart disease
• Peyronie's disease
• Neurological disease that may related to ED Patients were randomized equally categorized into three treatment groups. All the patients were blinded regarding the nature of the received medications.

Group (1) was given daily 3 g(three divided doses) oral tablets of L-arginine for eight weeks.

Group (2) was given daily 5 mg oral tablets of Tadalafil for eight weeks. Group (3) was given daily 3 g oral tablets of L-arginine and 5 mg oral tablets of Tadalafil for eight weeks.

Patients were advised to practice intercourse twice to three times weekly. They were assessed before and after eight weeks of treatment Pretreatment assessment

• History taking: including medical and surgical history.
• Sexual history: onset and duration of ED and Sexual health inventory for men (SHIM) to evaluate severity of ED.
• BMI
• General medical and local genital examinations.
• LABORATORY INVESTIGATIONS:

After 12 hours of fasting, venous blood samples were drawn from all included patients before and at the end of eight weeks of treatment for total serum testosterone assessments between 8.00 and 12.00 am.

• Penile ultrasonography: Shear Wave Elastography (SWE): is a current radiologic modality can measure biologic tissue elasticity and gives elastogram which superimposed on the B-mode ultrasound which expresses tissue stiffness in numbers(kpasc)

Follow up assessment:

• First follow up visit is scheduled after one week :to evaluate any adverse effect from the treatment
• 2nd follow up visit after 8 weeks : Reassessment to the SHIM questionnaire and serum testosterone and SWE.

Statistical analysis Data from the 3 groups will be collected, compared and statistically analyzed.

• Study Type: Interventional
• Enrollment (Actual): 180
• Phase: Phase 4

Contacts and Locations

Study Locations

• Egypt
  • Keman Fares
    • Fayoum, Keman Fares, Egypt, 63514
      • Mohamed Mahmoud Dogha

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• • Naive ( not previously treated) male patient with mild to moderate ED according to SHIM Questionnaire.

Exclusion Criteria:

• ● Kidney disease or liver failure

  • Coronary heart disease
  • Peyronie's disease
  • Neurological disease that may related to ED

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Quadruple

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Group A; was given daily 3 g(three divided doses) oral tablets of L-arginine for eight weeks	Drug: L-Arginine; get 3 gm oral tablets of L-arginine
Experimental: Group B; was given daily 5 mg oral tablets of Tadalafil for eight weeks.	Drug: Tadalafil 5 mg; get 5 mg oral tadalafil for 8 weeks
Experimental: Group C; was given daily 3 g oral tablets of L-arginine and 5 mg oral tablets of Tadalafil for eight weeks.	Drug: L-Arginine; get 3 gm oral tablets of L-arginine; Drug: Tadalafil 5 mg; get 5 mg oral tadalafil for 8 weeks

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
SHIM questionnaire	The SHIM (Sexual Health Inventory for Men) questionnaire is a commonly used tool for assessing erectile dysfunction (ED) in men. It is a brief, self-administered questionnaire that typically consists of five questions, with answers scored on a scale to help determine the severity of erectile dysfunction. The SHIM is widely used in both clinical practice and research to assess sexual health and function. Here are the key elements of the SHIM: Frequency of sexual activity (often using a scale from "almost never or never" to "almost always or always"). Confidence in maintaining an erection (again, on a similar scale). Ability to achieve an erection. Erection firmness (whether the erection is hard enough for penetration). Satisfaction with the firmness of the erection. The scores are typically aggregated into one overall score, and depending on the score, it classifies the degree of erectile dysfunction: 25-22: No erectile dysfunction 21-17: Mild erectile dysfunction 16-12: Mild to mod	8 weeks of treatment

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
testosterone level	androgenic hormone changes in response to treatment	8 weeks of treatment
Shear Wave Elastography	a current radiologic modality can measure biologic tissue elasticity and gives elastogram which superimposed on the B-mode ultrasound which expresses tissue stiffness in numbers(kpasc)	8 weeks of treatment

Collaborators and Investigators

• Sponsor: Fayoum University Hospital

Study record dates

Study Major Dates

• Study Start (Actual): January 14, 2024
• Primary Completion (Actual): January 1, 2025
• Study Completion (Actual): February 1, 2025

Study Registration Dates

• First Submitted: April 21, 2025
• First Submitted That Met QC Criteria: April 21, 2025
• First Posted (Actual): April 27, 2025

Study Record Updates

• Last Update Posted (Actual): April 27, 2025
• Last Update Submitted That Met QC Criteria: April 21, 2025
• Last Verified: April 1, 2025

More Information

Terms related to this study

• Keywords: erectile dysfunction , L-arginine , elastography
• Additional Relevant MeSH Terms: Urogenital Diseases; Genital Diseases; Mental Disorders; Genital Diseases, Male; Male Urogenital Diseases; Sexual Dysfunction, Physiological; Sexual Dysfunctions, Psychological; Erectile Dysfunction; Molecular Mechanisms of Pharmacological Action; Enzyme Inhibitors; Vasodilator Agents; Urological Agents; Phosphodiesterase 5 Inhibitors; Phosphodiesterase Inhibitors; Tadalafil
• Other Study ID Numbers: D 355

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No