Propionyl-L-carnitine (PLC) and acetyl-L-carnitine (ALC) Enhance the Effectiveness of Viagra (Sildenafil)

[Nelson Vergel]

Propionyl-L-carnitine (PLC) and acetyl-L-carnitine (ALC) have been shown to improve the effectiveness of sildenafil in treating erectile dysfunction, particularly in certain patient populations. Here are the key findings:

Effectiveness in Post-Prostatectomy Patients​

A study involving 96 patients who had undergone bilateral nerve-sparing radical retropubic prostatectomy found that the combination of PLC, ALC, and sildenafil was more effective than sildenafil alone. Specifically:

• The group receiving PLC (2 g/day) plus ALC (2 g/day) and sildenafil (100 mg as needed) showed significantly higher scores in erectile function, sexual intercourse satisfaction, orgasm, and general sexual well-being compared to the group using sildenafil alone.
• 28 out of 32 patients in the combination group achieved satisfactory sexual intercourse, compared to only 20 out of 39 in the sildenafil-only group.
• The combination therapy also significantly increased the percentage of patients with a positive intracavernous injection test (36.4% to 63.6%).

Efficacy in Diabetic Patients​

Another study focused on men with erectile dysfunction and diabetes who were unresponsive to sildenafil monotherapy. The results showed:

• After 24 weeks of treatment, patients receiving PLC (2 g/day) plus sildenafil (50 mg twice weekly) had significantly improved scores for achieving and maintaining erections compared to those using sildenafil alone.
• 70% of patients in the combination group reported a clinically significant improvement in erectile function, compared to only 20% in the sildenafil-only group.
• The combination therapy also resulted in a higher percentage of patients with improved erections (68% vs. 23%) and successful intercourse attempts (76% vs. 34%).

Safety and Tolerability​

Both studies reported that the combination of PLC and ALC with sildenafil was well-tolerated:

• The addition of PLC and ALC did not significantly increase the side effects of sildenafil.
• In the diabetic patient study, only two patients reported mild gastric pain in the combination group.

Dosage​

The recommended dosage used in these studies was:

• 2 g/day of acetyl-L-carnitine
• 2 g/day of propionyl-L-carnitine
• 100 mg of sildenafil once or twice a week

In conclusion, the addition of propionyl-L-carnitine and acetyl-L-carnitine to sildenafil therapy has shown promising results in improving erectile function, particularly in patients who have undergone prostatectomy or have diabetes. This combination appears to be safe and well-tolerated, offering a potential option for patients who may not respond adequately to sildenafil alone.

Improved Endothelial Function​

PLC and ALC help improve endothelial function, which is crucial for erectile function:

• They enhance nitric oxide (NO) production and bioavailability in the endothelium.
• This leads to better vasodilation and increased blood flow to the penis.

Enhanced Energy Production​

Both PLC and ALC play important roles in cellular energy metabolism:

• They facilitate the transport of fatty acids into mitochondria for energy production.
• This increased energy availability may improve the function of smooth muscle cells in the penis.

Antioxidant Effects​

PLC and ALC have antioxidant properties that can protect penile tissues:

• They reduce oxidative stress and free radical damage.
• This may help preserve the integrity of blood vessels and nerve tissues involved in erections.

Neuroprotective Properties​

ALC in particular has neuroprotective effects that may benefit erectile function:

• It supports nerve cell regeneration and repair.
• This can be especially beneficial for patients who have undergone prostatectomy or have diabetes-related nerve damage.

Synergistic Action with Sildenafil​

The combination of PLC and ALC appears to work synergistically with sildenafil:

• While sildenafil inhibits PDE5 to increase cGMP levels and promote smooth muscle relaxation, PLC and ALC improve the overall vascular and cellular environment.
• This multi-faceted approach may be particularly effective in patients who do not respond adequately to sildenafil alone.

Improved Testosterone Utilization​

Some research suggests that the PLC/ALC combination may improve testosterone utilization:

• This could contribute to enhanced libido and sexual function.
• The effect is comparable to testosterone supplementation in some studies.

By addressing multiple aspects of erectile physiology - from vascular function to energy metabolism and nerve health - PLC and ALC create a more favorable environment for sildenafil to exert its effects. This explains why the combination therapy has shown improved outcomes in clinical studies, particularly in challenging patient populations such as those with diabetes or post-prostatectomy erectile dysfunction.

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Citations:

1. Acetyl-L-carnitine plus propionyl-L-carnitine improve efficacy of sildenafil in treatment of erectile dysfunction after bilateral nerve-sparing radical retropubic prostatectomy - PubMed
2. Preliminary observations on the use of propionyl-L-carnitine in combination with sildenafil in patients with erectile dysfunction and diabetes - PubMed
3. Propionyl-l-carnitine: Health Benefits, Side Effects, Uses, Dose & Precautions
4. L-CARNITINE: Overview, Uses, Side Effects, Precautions, Interactions, Dosing and Reviews
5. WO2006050794A1 - Use of acetyl l-carnitine in combination with propionyl l-carnitine and sildenafil for the treatment of erectile dysfunction - Google Patents
6. Acetyl-l-carnitine plus propionyl-l-carnitine improve efficacy of sildenafil in treatment of erectile dysfunction after bilateral nerve-sparing radical retropubic prostatectomy
7. Combination therapy for erectile dysfunction: an update review