A validated LC-MS/MS assay for the quantification of phosphodiesterase-5 inhibitors in human plasma, Journal of Chromatography B, 1179, (122829), (2021). Sexual Dysfunction After Spinal Cord Injury, Current Sexual Health Reports, 12, 4, (244-250), (2020). Check if you have access through your login credentials or your institution to get full access on this article. Purchase this article to access the full text. Viagra is a prescription medicine used for erectile dysfunction (ED), which is difficulty in achieving and maintaining an erection. It is part of a class of drugs called phosphodiesterase-5 (PDE5) inhibitors.
Combined with sexual stimulation, Viagra works by increasing blood flow to the penis.
Which PDE5 inhibitor is the most effective in the treatment of erectile dysfunction in men with spinal cord injury? A systematic review and network meta‐analysis, Andrology, 13, 2, (314-322), (2024). Drug Repurposing for Spinal Cord Injury: Progress Towards Therapeutic Intervention for Primary Factors and Secondary Complications, Pharmaceutical Medicine, 37, 6, (463-490), (2023). Sexuality, Intimacy, and Reproductive Health after Spinal Cord Injury, Journal of Personalized Medicine, 12, 12, (1985), (2022). Autonomic Dysfunction in Neuromuscular Disorders, Neuromuscular Disorders, (97-117), (2022). Viagra is available as a tablet that is taken by mouth about one hour prior to sexual activity. Used in combination with sexual stimulation for erectile dysfunction. A generic form of sildenafil (marketed under the brand name Revatio) is used to treat pulmonary arterial hypertension (high blood pressure in the lungs). Viagra is a medication used to treat erectile dysfunction. Viagra belongs to a group of medications called PDE5 inhibitors. Viagra was discovered by the drug company Pfizer and was approved by the United States Food and Drug Administration (FDA) in 1998. For erectile dysfunction, Viagra is commonly prescribed. It is used for erectile dysfunction, in combination with sexual stimulation. The usual recommended dose is 50 mg taken once, as needed, about one hour prior to sexual activity.
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| Viagra Super Active | 100mg | 120 + 16 Pills | 198.37€ 188.92€ | |
| Viagra Generic | 100mg | 270 + 10 Pills | 270.47€ 257.59€ | |
| Viagra Oral Jelly | 100mg | 21 Sachets | 78.66€ 74.91€ | |
| Viagra Generic | 50mg | 10 Pills | 26.87€ 25.59€ | |
| Viagra Generic | 200mg | 10 Pills | 40.96€ 39.01€ | |
| Viagra Generic | 200mg | 60 + 4 Pills | 125.19€ 119.23€ | |
| Viagra Generic | 150mg | 10 Pills | 36.73€ 34.98€ | |
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| Viagra Generic | 50mg | 180 + 8 Pills | 158.82€ 151.26€ | |
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| Viagra Professional | 100mg | 180 + 4 Pills | 337.30€ 321.24€ | |
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However, Viagra can be taken anywhere from 4 hours prior to sexual activity up until 30 minutes prior to sexual activity. Do not exceed one tablet daily, regardless of the dosage. You can take Viagra with or without food. Your healthcare provider may change the dose if required—for example, to a lower dose of 25 mg, or a higher dose of 100 mg. Before taking Viagra, carefully read the prescription label and strongest viagra pill patient information leaflet. Ask your healthcare provider or pharmacist if you have any questions.
View all available purchase options and get full access to this article. Spinal cord injury: facts and figures at a glance. Birmingham, AL: National Spinal Cord Injury Statistical Center, July 1996. Neurological disturbances of sexual function with special reference to 529 patients with spinal cord injury. Andersson K-E, Wagner G.
Physiology of penile erection. The role of nitric oxide in the physiology of erection. Sildenafil: an orally active type 5 cyclic GMP-specific phosphodiesterase inhibitor for the treatment of penile erectile dysfunction. Sildenafil, a novel effective oral therapy for male erectile dysfunction. The design and analysis of sequential clinical trials.
Planning and evaluation of sequential trials, version 3. Ditunno JF Jr, Young W, Donovan WH, Creasey G. The international standards booklet for neurological and functional classification of spinal cord injury. Citation information is sourced cheap viagra online from Crossref Cited-by service. If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Your doctor will tell you how much medicine to use. For erectile dysfunction: Take this medicine about 1 hour before you have sex. Do not take it more than once a day.
Erectile Dysfunction CausesSome conditions are risk factors for erectile dysfunction (ED), including diabetes and heart disease. See a list of conditions and medicines that can cause ED. Penile Injections: A Patient GuideLearn how to administer a penile injection and get answers to common questions, including how the injected medication produces an erection. UCSF Health medical specialists have reviewed this information. It is for educational purposes only and is not intended to replace the advice of your doctor or other health care provider.
We encourage you to discuss any questions or concerns you may have with your provider. Objective: To evaluate the efficacy and safety of 50-mg doses of sildenafil during a 28-day period in patients with erectile dysfunction caused by spinal cord injury (cord level range, T6 through L5). Methods: To be included in this double-blind, placebo-controlled study, all patients had to be able to achieve at least a partial reflexogenic erectile response to penile vibratory stimulation. The study utilized a single triangular sequential trial design. A total of 27 patients were randomized to receive 50 mg of sildenafil or placebo, taken orally as required (not more than once daily) approximately 1 viagra online generic hour before sexual activity.
Results: After 28 days of treatment, nine of 12 patients (75%) on sildenafil and one of 14 patients (7%) on placebo reported that treatment had improved their erections (p = 0.0043). Furthermore, eight of 12 patients (67%) on sildenafil and two of 13 patients (15%) on placebo indicated that they wished to continue treatment (p = 0.018). A significant improvement in satisfaction with their sex life was reported by patients taking sildenafil (p = 0.012). No patients discontinued treatment due to adverse events. Conclusion: Oral sildenafil, taken as required (not more than once daily), significantly improves the quality of erections and satisfaction with sex life in men with erectile dysfunction caused by a spinal cord injury between T6 and L5. Always allow at least 24 hours between doses.
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Viagra only works in combination with sexual stimulation. You will not have an erection just by taking a tablet. Store the medicine at room temperature, away from heat, moisture, and direct light. Keep out of reach and out of sight of children and pets. Keep the bottle tightly closed when not in use. Do not share your medication with anyone. While taking Viagra, avoid alcohol and grapefruit juice. Also, do not take other medications that treat ED.
Select your manager software from the list below and click Download. Sexual Health After Neurological Disorders: A Comprehensive Umbrella Review of Treatment Evidence, Medical Sciences, 14, 1, (37), (2026). Evolving medical management of erectile dysfunction: recommendations from the Fifth International Consultation on Sexual Medicine (ICSM 2024), Sexual Medicine Reviews, 13, 4, (513-537), (2025). Sexual Dysfunction Following Spinal Cord Injury: Insights into Pathophysiology and Management Approaches, Journal of Surgery and Trauma, 13, 1, (1-7), (2025). Revolutionising Neurological Therapeutics: Investigating Drug Repurposing Strategies, CNS & Neurological Disorders - Drug Targets, 24, 2, (115-131), (2025). Viagra is only taken once as needed.
This medicine is not right for everyone.
Levitra works best 30 minutes to four hours after taking the pill. If you do not achieve an erection, you may need to increase the dosage. Levitra cannot be used with some medications. Take 10 mg of Cialis at least two hours before you are ready to engage in sexual activity. Cialis can be taken on a full stomach following meals and the effect of medication may last up to 36 hours.
If you do not achieve an erection on 10 mg, higher dosages can be taken, though you must consult your doctor regarding higher doses. Cialis cannot be used with some other medications. Flomax in doses of 0.4 mg is well tolerated. The most common side effects of oral medications for erectile dysfunction include headache, facial flushing and upset stomach. A small number of patients taking Viagra or Levitra may complain of a "blue cast" to their vision, sensitivity to light or blurred vision.
Cialis does not cause visual side effects. However, back pain and joint aches can occur with Cialis. Although Viagra, Levitra and Cialis have been shown to be effective in many men with erectile dysfunction, they are not effective in patients who have a prostatectomy, unless a nerve-sparing approach was used. These medications must not be used with medications containing nitrate, such as nitroglycerin, Nitrostat, Nitro-Bid, Nitro-Dur, Isordil and Ismo, or Deponit. Drugs Reported to Cause PriapismView a list of medications, drugs and conditions that may cause priapism, a prolonged and often painful erection. Do not use it if you have had an allergic reaction to sildenafil, Viagra, Revatio, or any ingredients in the medication. Do not take Viagra if you are taking a nitrate drug such as nitroglycerin tablets or isosorbide mononitrate. People who are taking a guanylate cyclase stimulator, such as Adempas (riociguat) or Verquvo (vericiguat), should not take Viagra. Tell your doctor if you are pregnant or breastfeeding, or if you have kidney problems, liver disease, bleeding conditions, eye or vision problems, a history of medical conditions of the penis, any type of blood pressure or heart problems, stomach bleeding, or blood diseases like sickle cell anemia or leukemia. Also, tell your doctor if you smoke. Tell any doctor who treats you that you take sildenafil. This medicine may cause the following problems:Low blood pressure (especially if taken with other medicines that lower blood pressure) and faintingHeart problems: if during sexual activity, you become dizzy or nauseous, or have pain or numbness in the chest, arms, neck, or jaw, stop immediately and get emergency medical help.Painful or prolonged erection (seek emergency medical help if an erection lasts more than 4 hours)Sudden vision loss or hearing problems, which require emergency medical care This medicine may cause the following problems: Low blood pressure (especially if taken with other medicines that lower blood pressure) and fainting Low blood pressure (especially if taken with other medicines that lower blood pressure) and fainting Heart problems: if during sexual activity, you become dizzy or nauseous, or have pain or numbness in the chest, arms, neck, or jaw, stop immediately and get emergency medical help.