Erections are a more delicate function than you might imagine, reflecting the overall state of your body. If you’ve recently felt “something is off,” understanding what’s happening in your body can deepen your understanding of how to address it.
How an erection occurs
An erection occurs when sexual stimulation is transmitted from the brain, through the nerves, to the penis, causing blood vessels to dilate and blood to flow in. This entire process involves blood vessels, nerves, hormones, and psychological state. If any of these are disrupted, it can manifest as difficulty achieving or maintaining an erection.
Erection quality is a barometer of vascular health
The blood vessels in the penis are particularly fine, and early changes in factors that affect systemic blood flow (such as arteriosclerosis, high blood pressure, and diabetes) tend to appear there sooner than in other parts of the body. A change like "it's been difficult to get an erection lately" can be an early warning sign from your body.
Factors affecting erections in daily life
| Factor | Effect |
|---|---|
| Lack of sleep / Chronic fatigue | Disrupts the balance of the autonomic nervous system, making it difficult for blood flow regulation necessary for erection to function properly. |
| Smoking | A common cause of vasoconstriction and poor blood circulation. |
| Lack of exercise / Obesity | Can affect both vascular health and testosterone secretion. |
| Excessive alcohol consumption | Temporarily affects blood flow and can lower the quality of erections. |
| Stress / Anxiety | Can directly impede erections via the autonomic nervous system. |
| Aging | Decreased vascular flexibility, gradual decline in testosterone secretion. |
What morning erections can tell you
If you experience erections during sleep (nocturnal penile tumescence), it often indicates that physical function itself is preserved. If problems only occur during sexual activity, psychological factors are likely involved. Conversely, if morning erections are generally absent, physical factors such as vascular, nerve, or hormonal issues should be considered.
What are ED medications for?
All ED medications currently in use belong to a group of drugs called PDE5 inhibitors. They work by dilating blood vessels in the penis when there is sexual stimulation, helping to maintain blood flow.
It's important to note that these drugs do not automatically cause an erection when taken. Their effect only appears with sexual stimulation. Many inquiries about "nothing happening after taking the drug" stem from this misunderstanding.
Differences between the three active ingredients (generic names)
| Generic Name | Onset of Action | Approximate Duration | Food Impact | Recommended Use |
|---|---|---|---|---|
| Sildenafil | 30 minutes to 1 hour | Approximately 4-5 hours | Susceptible (recommended to take on an empty stomach) | When timing of use is fixed |
| Vardenafil | 15-30 minutes | Approximately 5-8 hours | Moderate (avoid high-fat meals) | When rapid onset of action is prioritized |
| Tadalafil | 1-3 hours (gradual onset) | Up to 30-36 hours | Less susceptible | When flexibility in timing is desired |
It's more practical to choose based on whether you can adjust meal timings and when you want to use it, rather than "which is strongest." The way the effect appears varies among individuals, and the dosage or medication may be adjusted if sufficient effect is not achieved on the first try.
Main Side Effects
Side effects mainly stem from the vasodilating action and are mostly mild and temporary.
- Headache, facial flushing, nasal congestion: These are the most common side effects.
- Palpitations, indigestion, stomach discomfort
- Blurred vision, sensitivity to light, changes in color perception: Reported with sildenafil.
- Rare, severe side effects: Sudden vision loss (non-arteritic anterior ischemic optic neuropathy), sudden hearing loss. If these occur, stop taking the medication and seek medical attention immediately.
- Priapism: If an erection lasts for more than 4 hours, emergency medical attention is required as tissue damage may occur.
Who should not take it / Drugs that should not be combined
Those who meet the following criteria cannot take ED medication. Especially, combining with nitrates can cause a sudden, life-threatening drop in blood pressure and must be avoided.
| Category | Content |
|---|---|
| Contraindicated drugs | Nitrates/nitric oxide donors such as nitroglycerin, isosorbide dinitrate, amyl nitrite / Riociguat (for pulmonary hypertension) |
| Cardiovascular conditions | Individuals with cardiovascular disorders for whom sexual activity is deemed inappropriate, unstable angina, uncontrolled arrhythmia |
| Recent events | Individuals who have had a myocardial infarction, cerebral infarction, or cerebral hemorrhage within the last 6 months |
| Blood pressure | Hypotension (systolic blood pressure < 90 mmHg), uncontrolled hypertension |
| Other | Severe hepatic impairment, retinitis pigmentosa, history of hypersensitivity to the drug |
Even if you use angina medication "only when you have chest pain," it still falls under contraindications. Please inform your doctor about all medications you are currently taking or using as needed, including over-the-counter drugs and supplements.
Why can't I buy it at a drugstore?
ED medications are prescription drugs in Japan and are not sold over-the-counter at pharmacies or drugstores. Products sold through "personal import" online carry the following risks:
- Many are counterfeit, and may contain no active ingredient or more than indicated.
- They may contain impurities or unlisted ingredients.
- If health damage occurs, it is not covered by the Pharmaceutical Side Effect Relief System.
- They may be taken without checking for contraindications.
Even if it seems cheap, it's not worth the risk. Please obtain it through a medical institution.
Difference from supplements
Zinc, maca, tongkat ali, etc., are foods (supplements) and not pharmaceuticals. They cannot be expected to have a direct effect on blood vessels like ED medications, and are not a substitute for ED treatment.
While supplementing zinc can be beneficial if you are deficient, long-term excessive intake can hinder copper absorption and lead to anemia and neurological symptoms. Regarding testosterone, while age-related decline can contribute to symptoms, avoid using hormone preparations on your own judgment.
If a woman takes it
ED medication is not indicated for women, and its efficacy and safety have not been established. Side effects such as hypotension, headache, and flushing may occur, so women should not take it.
Conditions often confused with ED
- Intravaginal ejaculatory dysfunction: This is a condition where an erection is maintained, but ejaculation cannot occur within the vagina. It is not targeted by ED medication, and often involves stimulation methods or psychological factors.
- Decreased libido: Separate from erection problems; hormone levels, physical and mental state, and the effects of medications like antidepressants are checked.
- Premature ejaculation: Requires a different approach than ED medication.
Underlying diseases may be present
Because ED often manifests as a problem with penile blood vessels, it can be an early sign of systemic arteriosclerosis. Especially if you fall into any of the following categories, we recommend a health check-up or evaluation by an internist in conjunction with ED treatment:
- Diagnosed with diabetes, high blood pressure, or dyslipidemia, or have not had a health check-up.
- Smoking.
- Obese or lack exercise.
- Have been diagnosed with sleep apnea.
Also, medications you are taking, such as antihypertensives, antidepressants, or prostate medications, may be contributing to ED.
Online Consultation Process
ED medications can be prescribed through online consultation. You can consult from home, and the medication will be delivered to your specified address. During the consultation, in addition to your current symptoms, we will check your pre-existing conditions, medications you are taking (especially angina medication), blood pressure, and past surgical history. Please have your medication record at hand as we need to check for contraindications.
ED medications can be prescribed via online consultation. This is a private medical service (out-of-pocket expense). Please be sure to inform us of any medications you are taking, as some, like nitrates, cannot be combined.
