Erectile dysfunction drugs: Difference between revisions
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{{Hatnote|This page is about oral medications. For the injectable medication, see [[Trimix]].}} | |||
Several oral medications are available for treating erectile dysfunction (the inability to get or keep an erection). The four most common are '''sildenafil '''('''Viagra'''), '''tadalafil '''('''Cialis'''), '''avanafil '''('''Stendra'''), and '''vardenafil '''('''Levitra'''). These medications all improve blood flow to the penis when combined with sexual stimulation and are collectively known as '''phosphodiesterase 5 (PDE5) inhibitors'''. PDE5 inhibitors do not cause erections without sexual arousal, and do not increase arousal. | |||
PDE5 inhibitors all work the same way, so they have similar effects, risks, and risk mitigation strategies. However, they differ in how quickly and how long they work: | |||
{| class="wikitable" | |||
|+Differences between oral PDE5 inhibitors for treatment of erectile dysfunction | |||
!Drug | |||
!Common | |||
brand name(s) | |||
!Time to | |||
take effect<ref name=":0">{{Cite web |date=2014-05-12 |title=Which drug for erectile dysfunction? |url=https://www.health.harvard.edu/mens-health/which-drug-for-erectile-dysfunction |access-date=2025-11-17 |website=Harvard Health |language=en}}</ref> | |||
!Duration | |||
of effect<ref name=":0" /> | |||
!Instructions<ref>{{Cite web |title=What to know about oral meds for erectile dysfunction |url=https://www.mayoclinic.org/diseases-conditions/erectile-dysfunction/in-depth/erectile-dysfunction/art-20047821 |access-date=2025-11-17 |website=Mayo Clinic |language=en}}</ref> | |||
|- | |||
|Sildenafil | |||
|Viagra, Kamagra | |||
|30-60 minutes | |||
|4-5 hours | |||
|Take on an empty stomach before sex. High-fat foods and | |||
alcohol increase time to take effect | |||
|- | |||
|Tadalafil | |||
|Cialis, Cialis Daily, | |||
Adcirca | |||
|30-45 minutes | |||
|24-36 hours | |||
|Take with or without food before sex. Can also be prescribed | |||
as a lower dose taken daily for continuous effect. | |||
|- | |||
|Avanafil | |||
|Stendra, Spedra | |||
|15-30 minutes | |||
|6-12 hours | |||
|Take with or without food before sex. | |||
|- | |||
|Vardenafil | |||
|Levitra, Staxyn | |||
|30-60 minutes | |||
|4-5 hours | |||
|Take on an empty stomach before sex. High-fat foods and | |||
alcohol increase time to take effect | |||
|} | |||
== Background<!-- Provide background information for this drug. --> == | == Background<!-- Provide background information for this drug. --> == | ||
=== Mechanism of action === | === Mechanism of action === | ||
Oral erectile dysfunction medications increase blood flow (vasodilation) by inhibiting the enzyme phosphodiesterase 5 (PDE5).<ref>{{Cite web |title=Sildenafil |url=https://go.drugbank.com/drugs/DB00203 |access-date=2025-11-06 |website=go.drugbank.com |language=en}}</ref> They also inhibit PDE5 elsewhere in the body, particularly the lungs, and can cause systemic vasodilation. | |||
Erections occur when spongy tissue in the penis (the corpora cavernosa and corpus spongiosum) fill with blood, expand, and become rigid. The erectile tissue is surrounded by smooth muscle that is tonically (usually) contracted, and the muscle must relax (vasodilation) for sufficient blood to enter the penis. During arousal, the body increases production of cyclic guanosine monophosphate (cGMP), a molecule that triggers smooth muscle relaxation. Sildenafil increases the amount of cGMP in the corpora cavernosa by protecting cGMP from degradation by PDE5. Sildenafil has a similar molecular shape to cGMP and can bind strongly to PDE5, blocking cGMP from entering the enzyme's active site. | Erections occur when spongy tissue in the penis (the corpora cavernosa and corpus spongiosum) fill with blood, expand, and become rigid. The erectile tissue is surrounded by smooth muscle that is tonically (usually) contracted, and the muscle must relax (vasodilation) for sufficient blood to enter the penis. During arousal, the body increases production of cyclic guanosine monophosphate (cGMP), a molecule that triggers smooth muscle relaxation. Sildenafil increases the amount of cGMP in the corpora cavernosa by protecting cGMP from degradation by PDE5. Sildenafil has a similar molecular shape to cGMP and can bind strongly to PDE5, blocking cGMP from entering the enzyme's active site. | ||
== | === Other medical uses === | ||
In addition to erectile dysfunction, sildenafil is used to treat pulmonary arterial hypertension (a type of high blood pressure) in men and women.<ref>{{Cite web |title=Sildenafil (oral route) - Side effects & dosage |url=https://www.mayoclinic.org/drugs-supplements/sildenafil-oral-route/description/drg-20066989 |access-date=2025-11-06 |website=Mayo Clinic |language=en}}</ref> | |||
== Risks<!-- Describe the risks of this drug. --> == | == Risks<!-- Describe the risks of this drug. --> == | ||
| Line 38: | Line 78: | ||
== Risk mitigation<!-- Describe the risk mitigation for this drug. --> == | == Risk mitigation<!-- Describe the risk mitigation for this drug. --> == | ||
Erectile dysfunction drugs should never be used with [[poppers]] as together they can cause fatal drop in blood pressure. They should also not be used in combination with other medicines being used to treat blood pressure. | |||
If the user is feeling symptoms of low blood pressure: | If the user is feeling symptoms of low blood pressure: | ||
Latest revision as of 20:10, 16 November 2025
| Other names | sildenafil citrate, Viagra |
|---|---|
| Health risk | Mild |
| Addiction risk | Mild |
| Legal risk | Mild |
Several oral medications are available for treating erectile dysfunction (the inability to get or keep an erection). The four most common are sildenafil (Viagra), tadalafil (Cialis), avanafil (Stendra), and vardenafil (Levitra). These medications all improve blood flow to the penis when combined with sexual stimulation and are collectively known as phosphodiesterase 5 (PDE5) inhibitors. PDE5 inhibitors do not cause erections without sexual arousal, and do not increase arousal.
PDE5 inhibitors all work the same way, so they have similar effects, risks, and risk mitigation strategies. However, they differ in how quickly and how long they work:
| Drug | Common
brand name(s) |
Time to
take effect[1] |
Duration
of effect[1] |
Instructions[2] |
|---|---|---|---|---|
| Sildenafil | Viagra, Kamagra | 30-60 minutes | 4-5 hours | Take on an empty stomach before sex. High-fat foods and
alcohol increase time to take effect |
| Tadalafil | Cialis, Cialis Daily,
Adcirca |
30-45 minutes | 24-36 hours | Take with or without food before sex. Can also be prescribed
as a lower dose taken daily for continuous effect. |
| Avanafil | Stendra, Spedra | 15-30 minutes | 6-12 hours | Take with or without food before sex. |
| Vardenafil | Levitra, Staxyn | 30-60 minutes | 4-5 hours | Take on an empty stomach before sex. High-fat foods and
alcohol increase time to take effect |
Background
Mechanism of action
Oral erectile dysfunction medications increase blood flow (vasodilation) by inhibiting the enzyme phosphodiesterase 5 (PDE5).[3] They also inhibit PDE5 elsewhere in the body, particularly the lungs, and can cause systemic vasodilation.
Erections occur when spongy tissue in the penis (the corpora cavernosa and corpus spongiosum) fill with blood, expand, and become rigid. The erectile tissue is surrounded by smooth muscle that is tonically (usually) contracted, and the muscle must relax (vasodilation) for sufficient blood to enter the penis. During arousal, the body increases production of cyclic guanosine monophosphate (cGMP), a molecule that triggers smooth muscle relaxation. Sildenafil increases the amount of cGMP in the corpora cavernosa by protecting cGMP from degradation by PDE5. Sildenafil has a similar molecular shape to cGMP and can bind strongly to PDE5, blocking cGMP from entering the enzyme's active site.
Other medical uses
In addition to erectile dysfunction, sildenafil is used to treat pulmonary arterial hypertension (a type of high blood pressure) in men and women.[4]
Risks
Check the notes in the medication for side effects. Different "fillers" for tablets can have different side effects.
If it affects your blood pressure, it can make you feel spaced out and other symptoms (feeling weak, sick blurred vision, fainting), in this case you should stop further sexual and BDSM activities, and ensure you are somewhere safe in case you pass out.
If experiencing prolonged or painful erection, especially if it lasts for more than 2 hours, call emergency services[5].
Drug interactions
Addiction
Risk mitigation
Erectile dysfunction drugs should never be used with poppers as together they can cause fatal drop in blood pressure. They should also not be used in combination with other medicines being used to treat blood pressure.
If the user is feeling symptoms of low blood pressure:
- Seek medical attention
- Lay down
- Sitting up or standing up suddenly can worsen lightheadedness or cause fainting.
- Drink water
- Do not consume alcohol or other substances
Known incidents
Medical case reports
RACKWiki incident reports
References
https://www.nhs.uk/conditions/low-blood-pressure-hypotension/
- ↑ 1.0 1.1 "Which drug for erectile dysfunction?". Harvard Health. 2014-05-12. Retrieved 2025-11-17.
- ↑ "What to know about oral meds for erectile dysfunction". Mayo Clinic. Retrieved 2025-11-17.
- ↑ "Sildenafil". go.drugbank.com. Retrieved 2025-11-06.
- ↑ "Sildenafil (oral route) - Side effects & dosage". Mayo Clinic. Retrieved 2025-11-06.
- ↑ "Side effects of sildenafil". nhs.uk. 2022-03-03. Retrieved 2024-02-16.