How many types of erectile dysfunction medications (PDE5) are there? Comparing Sildenafil / Tadalafil / Avanafil, how do you choose?

💡 Short answer

PDE5 inhibitor medications (such as Sildenafil, Tadalafil) help increase blood flow to the penis, allowing for an erection when there is sexual stimulation. They are an effective and safe treatment for ED when used as directed by a physician. However, they are contraindicated in individuals taking nitrates or those with certain heart conditions, so it is important to consult a specialist before use. Self-medication is not advisable.

What are erectile dysfunction medications and how do they work?

The main group of medications used to assist with erections isPDE5 InhibitorsIt works by inhibiting the enzyme PDE5, which breaks down cGMP — a substance that causes blood vessels in the penis to dilate. When cGMP lasts longer, blood flows in better, resulting in improved erection.However, this group of medications requires sexual stimulation to take effect.It's not that it becomes hard immediately after taking it.

The infographic below summarizes what erectile dysfunction medications are, the PDE5 mechanism, and how to choose the right one for you.

ED medication, erectile enhancement drug 2

Sildenafil Tadalafil erectile dysfunction medications 3

PDE5 inhibitor, a medication that helps with erections.

How many types of PDE5 medications are there and how do they differ?

Medication	Start to take effect	Long-lasting effect	Highlights
Sildenafil	~30–60 minutes	~4–6 hours	Classic, affordable price, fatty foods interfere with absorption.
Tadalafil	~30–45 minutes	Up to ~36 hours.	Long-lasting effects, flexible timing, not significantly affected by food.
Avanafil	~15–30 minutes	~6 hours	Fast-acting, with usually fewer side effects.

The information above is an estimate. Individual responses may vary, and a doctor should evaluate and prescribe accordingly.

Which medication is suitable for whom?

I want it to take effect quickly for occasional use.Which is more suitable, Avanafil or Sildenafil?
I want to be flexible with time, no need to time it.Tadalafil (long-acting) meets the needs.
Have any underlying conditions/taking other medications:Always require a physician's assessment first.

Side effects and precautions

Common side effects are usually not severe, such as headaches, flushing, nasal congestion, or a burning sensation in the chest.Absolute contraindications:Do not use in conjunction with nitrates (heart disease/vasodilator medications) as it can cause severe life-threatening hypotension, and individuals with severe heart disease should consult a doctor beforehand.

Do not buy counterfeit/illegal medication online.Because it may contain harmful substances and the dosage may be uncertain, medication should only be obtained from a doctor or pharmacist.

What should I do if the medication hasn't worked?

If the medication is used correctly and still does not work, it may indicate that the cause is not solely related to blood vessels, such as low testosterone levels, stress, or nerve issues. You should consult a doctor for further evaluation.Find the true cause.which may need to be treated in conjunction with other methods, such asFocus Shockwaveto restore blood vessels or adjustHormonesRead more atTreating ED

Video: What symptoms can be treated with shockwave therapy for men's health?

Frequently Asked Questions (FAQ)

Why doesn't it get hard after taking the erectile dysfunction medication?

It may be due to the lack of sexual stimulation, taking it after a fatty meal which slows absorption, an inappropriate dose, or the cause not being vascular (such as low hormones, stress, or nerve issues). You should see a doctor to evaluate the cause.

Are erectile dysfunction medications dangerous?

If used as prescribed by a doctor and with no contraindications, it is considered safe. However, it must not be used in conjunction with nitrates under any circumstances, and individuals with heart disease or hypertension should consult a doctor beforehand. Avoid illicit drugs of unknown origin.

Can I buy erectile dysfunction medication online?

It is not recommended to purchase many medications sold online as they may be counterfeit or contaminated with harmful substances. You should obtain medications from a doctor or pharmacist who can assess their appropriateness and safety.

Do I have to take medication continuously?

It depends on the cause. If ED is due to factors that can be addressed (stress, hormones, behavior), treating the underlying issue may improve symptoms to the point where medication is no longer needed. The doctor will help develop a treatment plan targeting the root cause.

How much do erectile dysfunction medications cost?

It depends on the type and quantity of the pills. The clinic will assess and provide clear information beforehand. You can have a free initial consultation via LINE @mendical.

Genuine PDE5 medications from doctors vs counterfeit/illegal medications online.

Topic	Medication from a specialist doctor	Counterfeit/illegal online drugs
Source	Produced to standard, with a drug registration number.	No known source of production, no control.
Dosage	Of course, the doctor adjusts it to suit each individual.	It may vary, either too much or too little.
Safety	Undergo assessment of pre-existing conditions before dispensing.	May contain harmful substances, posing a risk to life.
Check contraindications (nitrates/heart disease)	The doctor always takes a medical history and conducts an examination first.	There is no screening, which poses a risk of severe blood pressure drops.
Follow-up	There is continuous care from the physician, and the plan can be adjusted.	There is no caregiver; you must handle any issues yourself.

The information is an estimate for comparison purposes. Results depend on each individual. A specialist should evaluate before making a decision.

Frequently Asked Questions about PDE5 Medications for Erectile Dysfunction

Is it dangerous or addictive to take PDE5 medications frequently?

PDE5 medications do not cause physical dependence, and when used correctly as prescribed by a doctor, they are considered safe for most people. However, excessive use without assessing the underlying causes may overlook hidden conditions such as diabetes or heart disease. Therefore, it is advisable to have a specialist evaluate the reasons for erectile dysfunction as well.

Why is it that after taking PDE5 medication, I still don't have an erection?

Common causes include improper eating habits, such as eating after fatty meals (which interferes with absorption), insufficient medication dosage, lack of sexual stimulation, or severe ED that pills cannot help. If adjustments in usage do not improve the situation, it is advisable to consult a doctor to consider other options, such as Focus Shockwave.

How do Cialis (Tadalafil) and Viagra (Sildenafil) differ?

Viagra has a short duration of action of about 4–6 hours, making it suitable for occasional use. In contrast, Cialis can last up to approximately 36 hours, providing more flexibility with timing and eliminating the need to time the dosage. The choice of the appropriate type should be determined by a doctor based on each individual's lifestyle and underlying health conditions.

Can I buy sex enhancement pills online? Is it safe?

It is highly discouraged. Many medications sold online are counterfeit or illegal, with unknown dosages and potentially harmful substances, which can lead to severe drops in blood pressure or heart failure. Medications should only be obtained from a doctor or pharmacist who has assessed your symptoms and underlying conditions.

Can a person with heart disease take ED medication?

Always consult a doctor first. A strict contraindication is to avoid using it in conjunction with nitrates (certain heart medications) as it can cause severe life-threatening drops in blood pressure. Individuals with heart disease should have their heart readiness assessed before using the medication. The doctor will choose the safest method tailored to the individual.

If taking ED medication hasn't resolved the issue, what should I do next?

If the pills are not effective, you should not increase the dosage on your own but should consult a urology specialist to identify the underlying cause. There may be other options that address the root cause, such as Focus Shockwave, which helps restore blood vessels, or testosterone replacement therapy if low hormone levels are found.

Erectile dysfunction medication (PDE5)How many types are there?Comparing Sildenafil / Tadalafil / Avanafil and how to choose the right one for you.