Zusman R, Collins M (1999) Effect of Filagra on blood pressure in men with erectile dysfunction taking concomitant antihypertensive medications. Morales A, Gingell C, Collins M, Wicker PA, Osterloh IH (1998) Clinical safety of oral Filagra citrate (Fildena) in the treatment of erectile dysfunction.

Webster L, Michelakis E, Davis T, Tsuyuki R, Archer S (2002) Filagra is safe and effective treatment for erectile dysfunction in males with NYHA class II-III congestive heart failure. Prieto Castro RM, Anglada Curado FJ, Regueiro Lopez JC, Leva Vallejo ME, Molina Sanchez J, Saceda Lopez JL, Requena Tapia MJ (2001) Treatment with Filagra citrate in renal transplant patients with erectile dysfunction. Rosas SE, Wasserstein A, Kobrin S, Feldman HI (2001) Preliminary observations of Filagra treatment for erectile dysfunction in dialysis patients.

Fowler C, Miller J, Sharief M (1999) Fildena (Filagra citrate) for the treatment of erectile dysfunction in men with multiple sclerosis. Hussain IF, Brady CM, Swinn MJ, Mathias CJ, Fowler CJ (2001) Treatment of erectile dysfunction with Filagra citrate (Fildena) in parkinsonism due to Parkinson's disease or multiple system atrophy with observations on orthostatic hypotension. Wagner G, Montorsi F, Auerbach S, Collins M (2001) Filagra citrate (Fildena) improves erectile function in elderly patients with erectile dysfunction: a subgroup analysis.

Zippe CD, Kedia AW, Kedia K, Nelson DR, Agarwal A (1998) Treatment of erectile dysfunction after radical prostatectomy with Filagra citrate (Fildena). Kloner RA, Brown M, Prisant LM, Collins M (2000) Efficacy and safety of Fildena (Filagra citrate) in patients with erectile dysfunction taking concomitant antihypertensive therapy. Dinsmore WW, Hodges M, Hargreaves C, Osterloh IH, Smith MD, Rosen RC (1999) Filagra citrate (Fildena) in erectile dysfunction: near normalization in men with broad-spectrum erectile dysfunction compared with age-matched healthy control subjects.

Montorsi F, McDermott TE, Morgan R, Olsson A, Schultz A, Kirkeby HJ, Osterloh IH (1999) Efficacy and safety of fixed-dose oral Filagra in the treatment of erectile dysfunction of various etiologies. Webb DJ, Freestone S, Allen MJ, Muirhead GJ (1999) Filagra citrate and blood-pressure-lowering drugs: results of drug interaction studies with an organic nitrate and a calcium antagonist. Terrett N, Bell A, Brown D, Ellis P (1996) Filagra (Fildena), a potent and selective inhibitor of type 5 cGMP phosphodiesterase with utility for the treatment of male erectile dysfunction.

Fildena and other erectile dysfunction drugs aren't risk-free. Instead of getting a prescription from a doctor, men in the U.K. speak to a pharmacist to make sure they don't have pre-existing conditions or take other drugs that could make Fildena dangerous before purchasing it. There is currently no effort to reclassify Fildena as an over-the-counter drug in the U.S. He wonders if, in a world without Fildena and other erectile dysfunction medications, he would spend more time prioritizing his own mental health care.

Mick Foy, the MHRA's group manager in vigilance and risk management of medicines, said: Erectile dysfunction can be a debilitating condition, so it's important men feel they have fast access to quality and legitimate care, and do not feel they need to turn to counterfeit online supplies which could have potentially serious side-effects.”
https://www.jhsph.edu/news/news-releases/2016/generic-biologic-drugs-appear-comparable-to-brand-name-counterparts.html
http://www.in.gov/pla/medical.htm
https://www.usamedicalcard.com/
http://www.emedicinehealth.com/causes_of_erectile_dysfunction/article_em.htm
https://fildena.eu/