DrThom banner bottom

       Registered with the Care Quality Commission

Viagra

Viagra - what is Viagra?
Viagra is the trade name for a drug called Sildenafil. Viagra is one of a class of drugs known as PDE-5 (Phosphodiesterase type 5) inhibitors. Viagra and the other PDE-5 inhibitors can help men with male impotence (erectile dysfunction) by enhancing the erectile response when a man is sexually stimulated. Aside from Viagra, the other drugs in this class are Cialis (Tadalafil) and Levitra (Vardenafil).
Viagra – is Viagra an aphrodisiac?
Viagra is not an aphrodisiac as it does not cause a man to be mentally sexually aroused. Viagra will only be effective if a man is mentally sexually aroused.
Viagra – how does Viagra work?
To understand how Viagra works you need to understand the mechanics of how a man gets an erection. When a man is sexually stimulated, the nervous system in the erectile tissue of your penis releases nitric oxide (NO). The nitric oxide stimulates an enzyme that produces a 'messenger' called cyclic guanosine monophosphate (cGMP). The cGMP causes the smooth muscle cells to relax. One result of this is that the arteries in the penis dilate and the blood can flow into the penis more easily. Another result is that the erectile tissue itself fills with blood. Both of these processes result in an erection. Viagra works by maintaining the level of cGMP in the smooth muscle cells. If you are not mentally sexually aroused, your brain will not stimulate the release of any nitric oxide and you will not produce increased levels of cGMP.
Viagra - is Viagra effective?
Clinical studies have shown that when compared to placebo, Viagra and the other drugs in the same class, result in significant improvement in erectile function. Although established to be a safe and effective drug, Viagra isn't appropriate for everyone and may not work in all cases.
Viagra – how does it affect blood pressure?
Viagra can slightly lower blood pressure. This is not a problem for most men, but Viagra's effect on blood pressure is exaggerated if the Viagra is taken with a nitrate drug. Nitrates are one of the treatments doctors prescribe for angina. If you take Viagra when you are also taking nitrates, the combined effect of the Viagra and the nitrates can lower your blood pressure to such an extent that it could prove fatal. Never take Viagra when taking nitrates.
Viagra – if I have a heart condition can I take it?
If you have a heart condition it is important that you discuss this with the doctor before taking Viagra. Your doctor may actually recommend abstaining from sexual activity for a while. If your doctor has prescribed nitrates, then for the reasons described above you must not take Viagra.
Viagra – can women take it?
Viagra is not licensed for use by women.
Viagra – how quickly does it work?
On average, Viagra becomes effective in just under an hour when you take a Viagra tablet on an empty stomach. Viagra can remain effective for between four and five hours. This does not mean that the erection will last that long - simply that you will have the ability to attain an improved erection for that period of time. If you take Viagra after a meal that has a high fat content, Viagra may take longer than an hour to become effective.
Viagra – why are there different doses?
Viagra is available in three dosages: 25mg, 50mg and 100mg. Some men may respond to a lower dose of Viagra. Some men may already be taking medicines, other than nitrates, that interact with Viagra and in these cases need to adjust the Viagra dosage.
Viagra – what dose is right for me?
The doctor needs to decide which dosage of Viagra is most appropriate. The doctor will take into account potential drug interactions, your age, the severity of your impotence and any previous experience you have had with Viagra.
Viagra - what if it does not work the first time I use it?
Viagra might not work the first time you take it for various reasons. Most doctors advise taking Viagra at least eight times before trying a different medicine.
Viagra - what are the side-effects?
Viagra's side-effects are generally mild and brief. Viagra's common side-effects are headache and facial flushing. Less frequently, men taking Viagra have reported indigestion, a stuffy nose and a blue tint to the vision.
Viagra - does it interact with other medicines?
Viagra interacts with many drugs. The following list is not complete but it is important to inform the doctor of all prescription and non-prescription medication taken, especially nitrate medications (e.g. glyceryl trinitrate (GTN), nitroglycerin, isosorbide mononitrate or dinitrate), nitroprusside, cimetidine, erythromycin, azole antifungals (e.g., itraconazole, ketoconazole), mibefradil, rifamycins (e.g., rifampicin), Alpha blockers (prescribed for prostate disease or high blood pressure), Ritonavir, and Amyl, Butyl or Isopropyl nitrates (“Poppers”).
Viagra - who shouldn't use it?
Men who have any of the following conditions should also avoid taking it: severe heart or liver problems, recent stroke or heart attack, low blood pressure, certain rare inherited eye diseases.
Viagra - does it treat the underlying causes of impotence?
No. Viagra will not resolve the underlying cause of male impotence although if the cause is primarily psychological, it may help to break the cycle of anxiety and failure associated with being unable to achieve a satisfactory erection. Hence, any man complaining of impotence must be investigated for possible underlying causes of the condition.
What kind of tests might highlight the underlying causes of male impotence?
Any man experiencing impotence should have his blood pressure measured to check for undiagnosed cardiovascular disease. Additionally, a blood test for diabetes should be performed along with cholesterol and triglyceride blood tests. It is becoming increasingly accepted and practised among doctors that sex hormone levels (testosterone) should also be checked by way of a blood test, particularly in older men and men with any chronic diseases.
What other oral impotence treatments are available?
The other medicines, Levitra and Cialis work in similar ways. Viagra is generally prescribed as the first line treatment. Cialis has a much longer half life than Viagra and Levitra and therefore its effect lasts much longer. This does not mean one has prolonged erections but the length of time available for further erections is increased without the need to take further doses. It also means however that the side effects if present will last longer. Levitra, like Cialis, can be taken with food whereas Viagra should be taken on an empty stomach. Some studies have shown Levitra to be more suitable for men suffering from diabetes.
Are there alternatives to oral medicines?
Alternative treatments include Caverject (“Alprostadil”) which is a medicine injected directly into the penis and MUSE (another form of “Alprostadil”) which is a pellet inserted into the urethra. These may be of use for men who have to take nitrates and are therefore unable to take the PDE5 inhibitors. The use of vacuum pumps and other mechanical devices for producing and maintaining erections are alternatives to taking prescribed medicines. These alternative treatments are not available online.
DrThom works in partnership with Terrence Higgins Trust, bpas and Lloydspharmacy   |  Pharmacy registration no: RPSGB 1094381

Chlamydia test | STI treatment | Herpes treatment | Impotence treatment |