Sildenafil Citrate, which is known under the brand name Viagra, has been keeps its leadership among the drugs for erectile dysfunction for 20 years today. Generic Viagra is used in men who can’t keep their erection long or strong enough for performing sexual intercourse. Based on the results of the study conducted at the Urology department of Boston University medical center, men taking generic Sildenafil succeeded in 69% of attempts at sexual intercourse compared to only 22% in patients on placebo.
Mechanism of action
The mechanism of action of generic Sildenafil is based on increasing the amounts of cyclic guanosine monophosphate (cGMP) by inhibiting phosphodiesterase type 5 (PDE5) secretion. Under the influence of sexual stimulation, the nerve endings in the penis secrete nitric oxide. It stimulates the growth of the amounts of cGMP in the smooth muscles of the blood vessels and the penis. Due to this, the muscular tissue becomes relaxed, and the arteries and veins widen thus improving the flow of blood to the penile area.
The increase in the amount of blood getting to the genitals results in a strong and durable erection, which lets men have normal sexual intercourse. However, the described mechanism may be triggered only by adequate sexual stimulation and the feeling of sexual arousal. Otherwise, the effect of generic sildenafil won’t be noticed.
Dosages and recommendations on usage
Generic sildenafil is produced in three dosages: 25mg, 50mg, and 100mg. In most cases, the doctors recommend using 50mg generic sildenafil as a starting dose. Yet if the effect turns out to be too strong or a patient has some major health condition, which demands caution when on sildenafil, or when a man is more than 65, then he may be advised to start with a 25mg pill of generic sildenafil.
On the contrary, when the desired effect is not achieved with the initially prescribed dose, a patient may be recommended to increase it to 100mg. This is the highest dose allowable for use per day.
One of the major questions the patients are interested in is how fast the drug starts working. The preparation comes into effect in about 30-60 minutes after the intake. Sildenafil should be taken only when you plan to have sex. This medication is not intended for daily use, but if there’s such a need take it not earlier than in 24 hours after the previous dose. Generic sildenafil action lasts for 4-5 hours, which is enough for performing several intercourses. What’s more, the refractory period gets significantly shorter when sildenafil is applied.
It is better to take the pill on an empty stomach as fatty foods can delay the onset of its action for 40-60 minutes.
Usage with caution
Some patients may be concerned with sildenafil usage when having some underlying health conditions. That’s why, to minimize any risks, every man should discuss the safety of the drug intake with his healthcare provider. Special attention should be paid to those with:
- Heart disease (e.g. aortic stenosis, unstable angina, coronary artery disease);
- Heart attack, a stroke or heart surgery within the last 6 months.
- Liver or kidneys problems;
- Cases of priapism (painful erection lasting over 4 hours) in medical history;
- Penis deformities;
- Uncontrolled high blood pressure;
It is not advised to consume generic sildenafil with excessive amounts of alcohol as it may lead to a loss of the drug’s efficiency or increased risks for side effects. Grapefruits and grapefruit juice may cause a rise in sildenafil concentration in the blood flow thus elevating the probability of overdose.
Some patients should never take generic sildenafil as they risk developing severe adverse effects on the drug or the safety of its usage hasn’t been properly studied in these patient groups. To the major contraindications to generic sildenafil application the following conditions belong:
- Age younger than 18;
- Cardiovascular diseases, which make excessive physical load dangerous;
- Known hypersensitivity to sildenafil or any other inactive components of the drug.
Possible side effects
According to the results of the study published in the “Urology” journal in 2000, 30% of patients taking sildenafil experience mild side effects. But speaking about the long-term safety of Sildenafil, only 3.8% had treatment-related unwanted reactions.
Among the major Sildenafil adverse reactions are:
- Facial flushing;
- Nasal congestion;
All these reactions are of a temporary character and disappear as soon as the effect of the drug finishes. However, there may happen some unwanted symptoms which demand immediate medical attention, for example:
- Heart attack signs (chest pain radiating to arms, back, and neck, irregular heartbeat);
- Vision changes (color blindness, blurred vision, double vision);
- Partial or complete vision loss;
- Hearing problems;
- A painful erection that wouldn’t go away for more than 4 hours.
Interaction with other drugs
Concomitant intake of generic sildenafil with a number of other drugs can result in the growth of risks for overdose or a severe drop in blood pressure. These medicines are as follows:
- Nitrate drugs (e.g. nitroglycerin);
- Some antifungals (e.g. itraconazole, ketoconazole);
- Alpha-blockers (e.g. prazosin, terazosin);
- Some antibiotics (e.g. erythromycin, clarithromycin);
- Other PDE5 inhibitors (e.g. tadalafil, vardenafil);
- HIV protease inhibitors (e.g. indinavir, ritonavir).
In the case of generic sildenafil overdose, it is important to contact your attending doctor for consultation as the probability of both moderate and severe adverse reactions (especially priapism) significantly grows. Experiencing any serious unwanted reactions turn for emergency medical help.
Generic sildenafil pills should be stored at room temperature away from moisture, heat, and light. Make sure the drug is out of reach of children and animals.
Only a few cases of Sildenafil-associated hepatotoxicity have been described throughout its 20-years-of-use history.
Viagra has no potential for addiction.