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A to Z of MS Sildenafil citrate

Product name

Viagra

Sildenafil citrate is an effective, well tolerated treatment for men with erectile dysfunction. The NICE Guideline suggests that men with MS with persisting erectile dysfunction should be offered 25-100mg sildenafil citrate unless there is a medical reason not to do so.

How sildenafil citrate works

Erectile dysfuntion is the inability to achieve or maintain an erection sufficient for satisfactory sexual performance. In multiple sclerosis this is commonly associated with bladder problems and both disorders are believed to be as a direct result of damage to the nerves in the spinal cord.

Whilst psychologically driven erections are likely to have been impaired by MS, reflex responses remain intact. Sildenafil works by delaying the action of enzymes called phosphodiesterases. This results in relaxing the blood vessels and allowing blood to flow into the penis on sexual stimulation.

How is sildenafil given

Sildenafil is taken orally one hour before sexual activity is planned; maximum dose frequency is once a day.

Side effects and contraindications

Prior to starting treatment the cardiovascular status of the individual should be assessed, as there is a degree of cardiac risk associated with sexual activity. Sildenafil can cause a mild and transient decrease in blood pressure and the impact of this should also be assessed before the drug is prescribed.

Most common side effects include headache, dizziness, flushing, rhinitis (nasal congestion) and dyspepsia (stomach pain). The only absolute contraindication to sildenafil is concurrent nitrate therapy.

Studies have shown that Viagra is not effective in treating women with sexual dysfunction in MS.

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