Lower numbers = closer to natural. Higher numbers = more enhanced.
Why this rating?
Tadalafil is an FDA-approved PDE5 inhibitor for erectile dysfunction, benign prostatic hyperplasia, and pulmonary arterial hypertension. It is not anabolic and does not raise testosterone. On cycle it is used as a support medication for erectile function, blood pressure/endothelial support, and 'pumps.' Not WADA prohibited. Rated 1 (basically natty): it is a vasodilator for erectile function, blood pressure, and 'pumps,' with no anabolic, fat-loss, or endogenous-hormone-raising action, so it does not move the natural muscular/physique/performance ceiling by any path, consistent with sildenafil and other PDE5 inhibitors on this scale.
Overview
A long-acting phosphodiesterase type-5 (PDE5) inhibitor, the drug in Cialis. It relaxes vascular smooth muscle, improving blood flow to the penis (erections), the prostate/bladder (urinary symptoms), and the vasculature generally (endothelial function, modestly lower blood pressure). Its long half-life makes it well suited to low-dose daily use, which is popular on cycle for erectile function, cardiovascular support, and 'better pumps.'
Important Warnings
- •NEVER combine with nitrates (nitroglycerin, isosorbide, 'poppers'/amyl nitrite). The combination can cause catastrophic, life-threatening hypotension. Because of tadalafil's long half-life, nitrates should not be given until at least 48 hours after the last dose.
- •Caution with alpha-blockers and other blood-pressure medications, additive hypotension.
- •An erection lasting more than 4 hours (priapism) is a medical emergency. Seek care immediately.
- •Stop and seek urgent care for sudden vision or hearing loss.
- •Alcohol adds to the blood-pressure-lowering effect, go easy when combining.
- •It does not raise testosterone or treat the hormonal causes of low libido. It is a blood-flow drug.
Purpose & Use Cases
Erectile Function On Cycle
Counters cycle-related erectile dysfunction: classically 'deca dick' from nandrolone/trenbolone (prolactin/progestin and blood-flow effects) and ED from crashed estrogen. A go-to support med for keeping erectile function intact.
Blood Pressure / Endothelial Support
Modestly lowers blood pressure and improves endothelial function, useful given the cardiovascular load androgens impose (though it is not a first-line antihypertensive).
BPH / Urinary Symptoms
FDA-approved for BPH; daily 5mg relieves lower-urinary-tract symptoms. Relevant because androgens can aggravate the prostate.
Pumps / Blood Flow
Enhanced vasodilation gives fuller 'pumps' and is used by some as a training/appearance aid, though this is a minor, non-anabolic effect.
Benefits
- Reliable erectile-function support, including cycle-induced ED
- Long half-life allows convenient low-dose daily use
- Improves endothelial function and modestly lowers blood pressure
- Relieves BPH / lower-urinary-tract symptoms
- Enhanced vasodilation / 'pumps'
- Non-hormonal; does not affect the HPTA
Good to Know
Low-dose daily does more than ED on a cycle
At 2.5-5mg/day, tadalafil (a PDE5 inhibitor) supports blood pressure and endothelial function, helps the erectile/libido dip from suppressive compounds, eases prostate/urinary symptoms, and improves pumps, which is why it is a common on-cycle staple, not just an ED drug.
Never combine with nitrates
PDE5 inhibitors plus nitrates (or other strong vasodilators) can cause dangerous hypotension. Its long half-life means the interaction window is long. This is the one hard rule.
Not prohibited
Tadalafil is not on the WADA list, so it is a freely-usable support compound for tested athletes, unlike most of what it is stacked with.
Dosage Guidelines
| Experience Level | Dosage Range |
|---|---|
| Beginner | 2.5 – 5 mg/day |
| Intermediate | 5 – 5 mg/day |
| Advanced | 5 – 20 mg/day |
Two dosing styles: a daily low dose (2.5-5mg) that keeps blood levels steady, favoured on cycle for continuous erectile/vascular/BPH support, or a larger as-needed dose (10-20mg) taken ahead of sexual activity. Because of the ~17.5h half-life it lingers far longer than sildenafil. Start low; the daily 5mg is the usual on-cycle choice. Alcohol adds to the blood-pressure-lowering effect.
Much longer than sildenafil/vardenafil (~4 hours), which is why tadalafil suits low-dose daily use.
Side Effects
Headache
commonThe most common side effect, from vasodilation.
Lower the dose; usually eases with continued use. Hydration helps.
Back / Muscle Pain
commonA characteristic tadalafil side effect (attributed to some cross-inhibition of PDE11), typically appearing 12-24h after dosing.
Usually self-limiting; lower the dose or switch PDE5 inhibitor if persistent.
Flushing / Nasal Congestion
commonFacial flushing and a stuffy nose from vasodilation.
Generally mild and transient.
Dyspepsia / Indigestion
commonHeartburn or stomach upset. FDA trial data show it occurring in roughly 4-10% of tadalafil users (vs 1-2% placebo), scaling with dose, on par with or more frequent than back pain.
Take with food; lower the dose.
Priapism
rareA painful erection lasting more than 4 hours: a medical emergency that can permanently damage tissue if untreated.
Seek emergency care immediately for an erection lasting >4 hours.
Sudden Vision / Hearing Loss (NAION)
rareRare reports of sudden decreased vision (non-arteritic ischemic optic neuropathy) or sudden hearing loss.
Stop and seek urgent care if sudden vision or hearing changes occur.
General Mitigation Strategies
Most side effects (headache, flushing, back pain) are mild, dose-dependent, and settle over time. Start low. The non-negotiable safety issue is the nitrate interaction (see warnings). Priapism and sudden vision/hearing loss are rare but emergencies. Because it lowers blood pressure, be careful stacking it with other antihypertensives, alpha-blockers, or alcohol.
Post Cycle Therapy (PCT)
Not hormonal. No PCT required. It supports erectile function but does not restore testosterone.
How It Works
Sexual stimulation releases nitric oxide, which raises cyclic GMP (cGMP) and relaxes smooth muscle. PDE5 is the enzyme that breaks cGMP back down; tadalafil inhibits PDE5, so cGMP persists and smooth-muscle relaxation/vasodilation is enhanced and prolonged. This improves penile blood flow (erections), relaxes smooth muscle in the prostate, bladder neck and urethra (relieving BPH/urinary symptoms), and improves systemic endothelial function with a modest blood-pressure-lowering effect. Chronic low-dose use has been shown to improve flow-mediated dilation (endothelial function). It has no hormonal or anabolic action whatsoever.
Fundamentals
Reference on the practices relevant to Tadalafil: how they are done and where they go wrong. Not a recommendation to use it.
Legal Status
FDA-approved prescription medication for erectile dysfunction, BPH, and pulmonary arterial hypertension.
Legal status varies by country and changes over time. This is a general summary, not legal advice.
WADA Status
Tadalafil (and PDE5 inhibitors generally) are not on the WADA Prohibited List and are permitted in and out of competition.