Some doctors prefer to start a man on the lowest dose of an oral medicine and increase the dose until an effective one is found. Others prefer to start with the highest dose and go to a lower dose only if a man complains of side effects. In either case, it’s important for a man to communicate with his doctor to let him know how the dose he’s using is working.

Branded Viagra can now be bought over the counter in pharmacies, but please check with your GP first if you have a medical condition. It's important to use a reputable pharmacy, as there is a large market in counterfeit drugs for erectile dysfunction, especially over the internet. These contain varying amounts of the active ingredient and sometimes completely different drugs.
Abstract | PubMed | Scopus (136) | Google ScholarSee all References Other candidate mechanisms linking ED and cigarette smoking include hypercoagulability and increased platelet aggregation, increased release of free fatty acids and catecholamines, changes in NO synthetic pathways, and a possible direct toxic effect on vascular endothelium.13x13Chung, WS, Shim, BS, and Park, YY. Hemodynamic insult by vascular risk factors and pharmacologic erection in men with erectile dysfunction: Doppler sonography study. World J Urol. 2000; 18: 427–430
There have been some studies to suggest that a placebo effect that improves ED may work for some men. One study found that men taking an oral placebo pill showed as much improvement in ED symptoms as men who took actual medication to improve ED. Conversely, men who were given therapeutic suggestions to improve ED did not see signs of symptom improvement.
Relation between erectile dysfunction prevalence and type of coronary syndrome (A). Time interval (months) between erectile dysfunction and coronary artery disease symptom onset in chronic coronary syndrome according to the number of vessels involved (B). ACS, acute coronary syndrome; CCS, chronic coronary syndrome, G1: ACS and 1-VD; G2: ACS and 2-,3-VD; G3: CCS. VD, vessel disease; C: the control group with normal coronary angiography. With permission from Montorsi et al.15
There are two kinds of surgery for ED: one involves implantation of a penile prosthesis; the other attempts vascular reconstruction. Expert opinion about surgical implants has changed during recent years; today, surgery is no longer so widely recommended. There are many less-invasive and less-expensive options, and surgery should be considered only as a last resort.
PubMed | Google ScholarSee all References In comparison, a study of 132 patients evaluated by penile duplex ultrasonography after intracorporeal papaverine injection found that hypertension alone was not an independent risk factor for vasculogenic ED.34x34Shabsigh, R, Fishman, IJ, Schum, C, and Dunn, JK. Cigarette smoking and other vascular risk factors in vasculogenic impotence. Urology. 1991; 38: 227–231
Crossref | PubMed | Google ScholarSee all References Regular exercise can significantly decrease the patient's risk of having a myocardial infarction during sexual intercourse by increasing the patient's functional reserve, decreasing the heart rate, and increasing the stroke volume.8x8Muller, JE, Mittleman, A, Maclure, M, Sherwood, JB, Tofler, GH, and Determinants of Myocardial Infarction Onset Study Investigators. Triggering myocardial infarction by sexual activity: low absolute risk and prevention by regular physical exertion. JAMA. 1996; 275: 1405–1409
According to the Cleveland Clinic, “because erectile dysfunction is caused by a complex set of psychosocial, neurologic, and vascular factors, a specific cause in a patient may remain ambiguous.” The root causes are often related to a blockage or dysfunction of blood vessels. For example, ED can be due to conditions like atherosclerosis or diabetes, hormonal imbalances or problems related to mental health. It’s been found that common causes typically include one or more of the following factors: (2)

Abstract | Full Text | Full Text PDF | PubMed | Scopus (53) | Google ScholarSee all References Coital position has not been shown to play a role in increased cardiovascular risk; similar peak heart rates and blood pressure levels are evident with either the man or the woman in the superior position during intercourse.90x90Nemec, ED, Mansfield, L, and Kennedy, JW. Heart rate and blood pressure responses during sexual activity in normal males. Am Heart J. 1976; 92: 274–277
Gutiérrez-González, Enrique; Castelló, Adela; Fernández-Navarro, Pablo; Castaño-Vinyals, Gemma; Llorca, Javier; Salas-Trejo, Dolores; Salcedo-Bellido, Inmaculada; Aragonés, Nuria; Fernández-Tardón, Guillermo; Alguacil, Juan; Gracia-Lavedan, Esther; García-Esquinas, Esther; Gómez-Acebo, Inés; Amiano, Pilar; Romaguera, Dora; Kogevinas, Manolis; Pollán, Marina; Pérez-Gómez, Beatriz. “Dietary Zinc and Risk of Prostate Cancer in Spain: MCC-Spain Study.” Nutrients. Jan 2019, 11(1).
In the vessels that supply the heart, healthy arteries enlarge in diameter up to 50% during exercise when sufficient nitric oxide is present. Because of its brief half-life, a continual supply of nitric oxide is required for optimal effect. If the supply of nitric oxide is inadequate, endothelial dysfunction—a core factor in heart disease—is made worse. Endothelial dysfunction can trigger the growth of coronary plaque.8

Consider this:  penicillin, the first successful antibiotic, was derived from molds that inhibit bacterial growth.  Scientists had to figure out why the molds slowed bacteria, and refine the active ingredients.  Using herbal supplements is somewhat like putting mold on a wound.  It might help, a little, but it’s certainly not going to help as much as using penicillin.
In men without cardiovascular disease, erectile dysfunction (ED) pills are very safe. The three rivals -- Viagra, Cialis, and Levitra -- have similar side effects, including headache, facial flushing, nasal congestion, diarrhea, backache, and, in a few Viagra or Levitra users, temporary impaired color vision (men with retinitis pigmentosa, a rare eye disease, should check with their ophthalmologists before using these medications).
Alprostadil self-injection. With this method, you use a fine needle to inject alprostadil (Caverject Impulse, Edex) into the base or side of your penis. In some cases, medications generally used for other conditions are used for penile injections on their own or in combination. Examples include papaverine, alprostadil and phentolamine. Often these combination medications are known as bimix (if two medications are included) or trimix (if three are included).
For oral erectile dysfunction medicines to work as desired, they must be used properly in the first place. This means taking the medicine 30–45 minutes before engaging in sexual intimacy; taking the drug on an empty stomach or at least avoiding a heavy or high-fat meal before taking the drug (this is especially important when using sildenafil); and engaging in adequate genital stimulation before attempting intercourse. Drinking small amounts of alcohol (one to two drinks) should not compromise the effectiveness of erectile dysfunction medicines, but larger amounts of alcohol can diminish a man’s ability to have an erection.
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