Getting the most out of ED medications

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There are three oral medications approved for the treatment of erectile dysfunction: sildenafil (Viagra), vardenafil (Levitra), and tadalafil (Cialis). All three belong to a class of drugs called phosphodiesterase-5 (PDE5) inhibitors. Sildenafil (Viagra), vardenafil (Levitra), and tadalafil (Cialis) block the PDE-5 enzyme, which prolongs the nerve signal that causes an erection. The result is increased blood flow into the penis and an improved erection. The medications cannot cause an erection unless the nerve signal is activated by sexual arousal.

Who are Good Candidates for PDE5 Inhibitors?

PDE5 Inhibitors are a good choice for men at any age and in any ethnic group who are in good health and who do not have conditions that preclude taking it (such as the use of nitrates or alpha-blockers; see "Who is not a good candidate for PDE-5 inhibitors" on this same page.)

Maximizing the effectiveness of PDE5 Inhibitors

Tadalafil (Cialis)

How and when

Tadalafil can work as quickly as 30 minutes after it is taken, but most patients will see improvement in erections after one hour. It reaches a maximum level in the blood in 2 hours, so men should try to time intercourse around 2 hours after they first take the drug. The drug is absorbed about 10% better if it is taken with a small amount of food. If it works at two hours, men might find that it works faster, and they might find that it improves their erections for 24-36 hours. If the medication lasts 24-36 hours, then men can take it hours before they plan to have sex. For example, men who wish to have intercourse first thing in the morning might take the medicaton at bedtime, and count on it still working when they wake up the next morning. This may allow more spontaneity, so men don't have to worry that they are "running out of time" to have sex.

Dosing

Many younger men will respond to the 10 mg dose, but most older men require the 20 mg dose. The side effects are similar between the 10 and 20 mg doses. We have had some patients who get improvement with higher doses, but the amount of improvement with higher doses is small, and the risk of side effects is higher, so men should check with their doctor before trying a dose higher than 20 mg.

Side Efffects

The side effects that are common with the various ED medications are headache (15%), facial flushing (10%) and stomach upset (7%). The only side effect that is unique to Tadalafil is back pain, which is usually mild and can last up to 4 hours.

Drug Interactions

Tadalafil, like all of the similar ED meds, should never be taken with nitroglycerine, or longer-lasting heart medications called nitrates. The most commmon medication is called isosorbide, and it is given to men to prevent angina. Tadalafil is safe to take with the BPH medications Flomax or Uroxatral, but caution should be used if a patient takes a BPH medications such as terazosin or doxazosin. Men who take medication for BPH should consider a minimally-invasive prostate treatment to improve their symptoms so they don't need to take BPH medictions.

Vardenifil (Levitra)

How and when

Vardenifil works the quickest of the three ED medications; many men will see an effect within 15 minutes after taking the pill. Vardenafil works best if it is taken on an empty stomach. The peak level is reached one hour after the medication is taken, so men should try to time intercourse around 1 hour after they first take the drug. If it works after one hour then men may find that it works faster, and they may find benefit for up to six hours after taking the drug.

Dosing

Many younger men will respond to the 10 mg dose, but most older men require the 20 mg dose. The side effects are similar between the 10 and 20 mg doses. We have had some patients who get improvement with higher doses, but the amount of improvement with higher doses is small, and the risk of side effects is higher, so men should check with their doctor before trying a dose higher than 20 mg.

Side Efffects

The side effects that are common with the various ED medications are headache (15%), facial flushing (10%) and stomach upset (7%).

Drug Interactions

Vardenafil, like all of the similar ED meds, should never be taken with nitroglycerine, or longer-lasting heart medications called nitrates. The most commmon medication is called isosorbide, and it is given to men to prevent angina. Vardenafil should be used with caution if a patient takes any of the followingg BPH medications

Flomax, Uroxatral, terazosin, or doxazosin. Men who take medication for BPH should consider a minimally-invasive prostate treatment to improve their symptoms so they don't need to take BPH medictions.

Sildenafil (Viagra)

How and when

Sildenafil works within 30-60 minutes after it is taken. Sildenafil works best if it is taken on an empty stomach. The peak level is reached one hour after the medication is taken, so men should try to time intercourse around 1 hour after they first take the drug. If it works after one hour then men may find that it works faster, and they may find benefit for up to four hours after taking the drug.

Dosing

Many younger men will respond to the 50 mg dose, but most older men require the 100 mg dose. The side effects are similar between the 50 and 100 mg doses. We have had some patients who get improvement with higher doses, but the amount of improvement with higher doses is small, and the risk of side effects is higher, so men should check with their doctor before trying a dose higher than 100 mg.

Side Efffects

The side effects that are common with the various ED medications are headache (15%), facial flushing (10%) and stomach upset (7%). A small number of men who use Sildenafil will have "blue vision" for several hours after they take the medication.

Drug Interactions

Sildenafil, like all of the similar ED meds, should never be taken with nitroglycerine, or longer-lasting heart medications called nitrates. The most commmon medication is called isosorbide, and it is given to men to prevent angina. Sildenafil should be used with caution if a patient takes any of the following BPH medications

Flomax, Uroxatral, terazosin, or doxazosin. Men who take medication for BPH should consider a minimally-invasive prostate treatment to improve their symptoms so they don't need to take BPH medictions.

Who is not a good candidate for PDE-5 inhibitors?

PDE5 inhibitors aren't suitable for everyone. Those taking nitrate drugs for angina should never take any of the PDE-5 inhibitors. Men with the following conditions should talk with their primary care doctors before taking any of the ED drugs.

What to do if the medications don't work

It is not a reason to give up if the medications don't work the first time a man tries them. It is very common for this to happen for a variety of reasons. Sometimes their can be anxiety about the medication, fear of side effects, anxiety about being able to perform, or other reasons. Men should try to relax, and try the medication several times before giving up. The first time a man takes one of the medications he might intentionally take it when he doesn't intend to have sex so that he can see if he will have any side effects. Try some of the following tips if the medications don't work.