Sildenafil Citrate: How To Use, Important Info, Contraindications & Interactions

Sildenafil (also known as Viagra) is indicated for use in the treatment of erectile dysfunction due to the inability to achieve or maintain an erection necessary for satisfactory sexual intercourse. It contributes to achieving an erection, but at the same time, it has no therapeutic effect on dysfunction since it acts symptomatically.

The action of the drug is determined by the ability of the active ingredient to inhibit phosphodiesterase 5, which is involved in the breakdown of cyclic guanosine monophosphate, necessary for relaxing the muscles of the cavernous body. When the muscles of the cavernous body relax, blood flow in the male genital organ improves, its size increases, and erectile function normalizes. An important component for the onset of an erection is nitric oxide, the relaxing effect of which is enhanced by sildenafil. The positive effect of taking the medication is observed only in the case of sexual stimulation.

In absolutely healthy people, the remedy does not cause any negative reactions. Sildenafil can be used by any men who have problems in erectile function, whether it is a psychological disorder, physiological or mixed.

Contraindications for use

Before using Sildenafil tablets, make sure you have no contraindications for use:

  • the drug should not be used by patients who take donate nitric oxide, organic nitrates or nitrites in any form since sildenafil enhances the hypotensive effect of nitrates;
  • according to the registered indication, this medication is not intended for use in children and adolescents under the age of 18 years;
  • according to the registered indication, the drug is not intended for use in women;
  • lactase deficiency, lactose intolerance, glucose-galactose malabsorption;
  • simultaneous use of sildenafil with ritonavir is not recommended;
  • hypersensitivity to the drug.

The safety and efficacy of Sildenafil, when combined with other drugs for treating erectile dysfunction, have not been studied, so such combinations are not recommended.

With caution:

  • diseases involving bleeding;
  • exacerbation of gastric ulcer and duodenal ulcer;
    episodes of development of anterior non-arteritis ischemic neuropathy of the optic nerve (in history);
  • anatomical deformity of the penis (angulation, cavernous fibrosis or Peyronie’s disease);
  • diseases predisposing to the development of priapism (sickle cell anemia, multiple myeloma, leukemia, thrombocythemia);
  • hereditary retinitis pigmentosa;
  • heart failure, unstable angina, suffered myocardial infarction, stroke or life-threatening arrhythmias, arterial hypertension or hypotension in the last 6 months.

Interactions with other drugs

  • Simultaneous use of inhibitors of CYP3A4 (erythromycin, cimetidine reduces the clearance of sildenafil and increases its concentration in the blood plasma;
  • Simultaneous use of indinavir, saquinavir, ritonavir, increases Cmax in plasma and AUC of sildenafil, which is caused by inhibition of CYP3A4 isoenzyme under the influence of indinavir, saquinavir, ritonavir;
  • CYP3A4 isoenzyme inhibitors, such as ketoconazole or itraconazole, can increase the concentration of sildenafil in plasma;
  • Simultaneous use with nitrates enhances the hypotensive effect of nitrates;
  • A single dose of the ED drug can cause rhabdomyolysis in a patient receiving simvastatin.

How to use Sildenafil Citrate?

It’s recommended to take 1 tablet of the drug 1 hour before sexual intercourse. The recommended dosage is 50 mg per day. Depending on the individual factors, the dosage of the drug can be increased to 100 mg per day or reduced to 25 mg per day. It all depends on the individual tolerance and the result. Older men should clearly follow the instructions. It should be noted that 100 mg is the maximum daily dosage. Never exceed the dosage prescribed by a doctor. A higher dose will not enhance the effect but will cause side effects. If you want the tablet to act faster, it is recommended to take it before meals. To ensure the effectiveness of the medication, sexual stimulation is required. Most often, the pattern of pill use is prescribed by a doctor.

Other important information for those who take Sildenafil

In the majority of studied cases, Sildenafil does not cause negative reactions. Still, the following side effects can occur:

  • insomnia;
  • headache and vertigo;
  • increased muscle tone;
  • soreness of the joints and muscles;
  • nausea or vomiting;
  • violation of colors, clarity, sharpness of view;
  • respiratory disorders.

There were rare cases when men reported a painful or excessively long erection that lasted more than 4 hours. If this happens to you, consult a doctor immediately. Do not combine Sildenafil with grapefruit or grapefruit juice, as this may interfere with the normal action of the drug. If you have not had an erection for quite a long time, then you may need several attempts. Taking a lot of alcohol can also make it difficult to achieve an erection. This product is not an aphrodisiac. It does not affect sexual desire or libido. Thus, it cannot cause an erection in the absence of a stimulus. If a person does not have erectile dysfunction, these tablets will not affect his erection.