Tadalafil
Also known as: Cialis · Adcirca · Alyq
A long-acting PDE5 inhibitor originally developed for erectile dysfunction, now widely used for cardiovascular health, blood flow optimization, prostate health, and exercise performance.
Overview
Tadalafil is a phosphodiesterase type 5 (PDE5) inhibitor that has transcended its original indication for erectile dysfunction to become one of the most versatile compounds in health optimization. By inhibiting PDE5, tadalafil prevents the breakdown of cyclic GMP (cGMP), leading to smooth muscle relaxation and vasodilation throughout the body. Its uniquely long half-life (~17.5 hours) allows for daily low-dose use that provides continuous benefits. Daily low-dose tadalafil (2.5-5 mg) has become a staple in many optimization protocols. Beyond sexual function, it improves endothelial function and blood flow to all tissues, reduces blood pressure, improves exercise capacity, treats benign prostatic hyperplasia (BPH), and may have neuroprotective effects.
Research suggests benefits for insulin sensitivity, pulmonary arterial hypertension (FDA-approved as Adcirca), and even Raynaud's phenomenon. The cardiovascular benefits are particularly noteworthy — improved NO/cGMP signaling supports vascular health, and some studies suggest reduced cardiovascular mortality risk.
Mechanism of Action
Selectively inhibits phosphodiesterase type 5 (PDE5), preventing degradation of cyclic guanosine monophosphate (cGMP). This amplifies nitric oxide (NO) signaling, causing smooth muscle relaxation and vasodilation in penile corpus cavernosum, pulmonary vasculature, prostate, and bladder. Also inhibits PDE11 to a lesser degree. Improves endothelial function and reduces arterial stiffness.
Key Benefits
Potential Side Effects
Common Stacks
This peptide is commonly combined with the following compounds for synergistic effects:
Known Interactions
The following interactions have been documented for Tadalafil. Always consult a healthcare professional before combining compounds.
Synergistic (2)
Testosterone optimizes libido and hormonal drive while tadalafil ensures vascular function for erectile performance. Commonly used together in men's health protocols.
PT-141 works centrally (brain) to increase sexual desire while tadalafil works peripherally (vasculature) to support erectile function. Complementary mechanisms.
Scientific References
Quick Reference
Typical Dose
2.5-5 mg daily (optimization); 10-20 mg as needed (ED)
Frequency
Once daily (low-dose); as needed (higher dose)
Route
Oral tablet
Half-Life
~17.5 hours
Cycle Length
Ongoing for daily use; as needed for acute use
FDA Status
FDA approved (Cialis for ED/BPH; Adcirca for pulmonary arterial hypertension)
Need to calculate dosing?
Use our reconstitution calculator to determine exact syringe measurements.
Open CalculatorThis information is for educational purposes only. Consult a qualified healthcare professional before using any peptide. Dosing information reflects commonly reported protocols and may not be appropriate for everyone.
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