Sildenafil Citrate for Women Volume 1 - Issue 5

Mohamed Nabih EL Gharib*

• Department of Obstetrics & Gynecology, Tanta University, Egypt

Received: October 03, 2018;   Published: October 09, 2018

Corresponding author: Mohamed Nabih EL-Gharib, Professor of Obstetrics & Gynecology, Faculty of Medicine, Tanta University, Egypt

DOI: 10.32474/OAJRSD.2018.01.000124

Abstract PDF

Sildenafil citrate (SC) is a medicinal drug used to treat male erectile dysfunction and pulmonary hypertension. Sildenafil is a selective and potent competitive inhibitor of the cyclic guanosine monophosphate (cGMP) -specific phosphodiesterase-type 5 (PDE-5) enzymes, which, by preventing the breakdown of cGMP, potentiate the action of NO in tissues that contain PDE-5. Thus, increasing vasodilatation and potentiating the effects of nitrous oxide (NO) on the vascular smooth muscle [1-2]. SC increases uterine blood flow and potentiates estrogen-induced vasodilatation [3]. Sildenafil citrate is metabolized is in the liver by cytochrome P450, the metabolites are: N-desmethylsildenafil (about 50% potency for PDE5). The biological half-life is from 3 to 4 hours, it is excreted in feces and in urine [4].

Sildenafil is developing as a potential applicant for the treatment of intrauterine growth retardation and for premature labor [5]. Sildenafil has also been proposed as a potential therapeutic strategy to maintain placental function in pre-eclampsia [6]. Should sildenafil citrate possess vasodilatory effects in the feto-placental circulation, this would significantly enhance its therapeutic use in treating placental insufficiency. SC has recently been demonstrated not to alter the contractile response to vasoconstrictors or to endothelial dependent vasodilators. In non-pregnant females, SC causes uterine artery vasodilation therefore it also be employed to treat menstrual pain and muscle spasms [7]. SC is increasingly used in the pregnant patient for the treatment of pulmonary hypertension [8]. Its safety and efficacy combined with its lack of teratogenic or feto-toxic effects mean that its use for the treatment of pulmonary hypertension in pregnancy is likely to increase [9].

The most common adverse effects of sildenafil citrate use include: headache, flushing, indigestion, nasal congestion, and impaired vision, including photophobia and blurred vision. Some complained of blurriness and loss of peripheral vision. In July 2005, the FDA found that sildenafil could lead to vision impairment in rare cases [and several studies have linked sildenafil use with non-arteritic anterior ischemic optic neuropathy [10]. The FDA announced that all PDE5 inhibitors, including sildenafil, required a more prominent warning of the potential risk of sudden hearing loss [11]. Vaginal sildenafil might be an interesting therapeutic option before conception in women with histories of reproductive failure [12]. In addition, intravaginal sildenafil citrate tablets used as suppositories might be a new, interesting, safe antiabortive option in the treatment of threatened miscarriage in patients with a history of unexplained recurrent spontaneous abortion. The dose intravaginal sildenafil citrate is 25 tablets given 3- 4 times daily [13]. Oral dosage of SC is 50mg per day [14].

Figure 1: The international index of erectile function questionnaire [17].

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