Vardenafil's indications and contraindications are the same as with other PDE5 inhibitors; it is closely related in function to
sildenafil citrate (Viagra) and
tadalafil (Cialis). The difference between the vardenafil molecule and sildenafil citrate is a
nitrogen atom's position and the change of sildenafil's
piperazine ring
methyl group to an
ethyl group. Tadalafil is structurally different from both sildenafil and vardenafil. Vardenafil's relatively short effective time is comparable to but somewhat longer than sildenafil's. Vardenafil also does not have an effect on PDE6, which means that it does not have vision adverse effects.
Beyond its indications for erectile dysfunction, vardenafil may be effective in the treatment of
premature ejaculation, where it may significantly increase the time from penetration to ejaculation.[3]
Adverse reactions
The common, adverse drug reactions (side effects) are the same as with other PDE5 inhibitors. The frequent vardenafil-specific side-effect is
nausea; the infrequent side effects are abdominal pain, back pain,
photosensitivity, abnormal vision, eye pain, facial
edema,
hypotension, palpitation,
tachycardia,
arthralgia,
myalgia, rash, itch, and
priapism.
One possibly serious, but rare, side effect with vardenafil is
heart attack. Also, in rare cases, vardenafil use may cause priapism, a very painful emergency condition that can cause impotence if left untreated.[4]
Vardenafil should not be used by people taking
nitrate medications, because combining them with vardenafil might provoke potentially life-threatening
hypotension (low blood pressure).[6][7]
Further, vardenafil causes lengthening of the
QT interval. Therefore, it should not be taken by people taking other medications that affect the QT interval (such as
amiodarone).[8][9]
History
Vardenafil was co-marketed by
Bayer Pharmaceuticals,
GlaxoSmithKline, and
Schering-Plough under the brand name Levitra. As of 2005, the co-promotion rights of GSK on Levitra have been returned to Bayer in many markets outside the US. In Italy, Bayer sells vardenafil as Levitra and GSK sells it as Vivanza. Thus, because of European Union trade rules,
parallel imports might result in Vivanza sold next to Levitra in the EU.
An orally disintegrating form, marketed as Staxyn and Levitra Soft, has been gaining approvals in countries such as the United States[10] and Canada.[11]
Tainted supplements
The US
Food and Drug Administration (FDA) has found vardenafil and other synthetic PDE5 inhibitors in numerous products marketed as "herbal" supplements or "all natural" products for male enhancement.[12][13]
^Aversa A, Pili M, Francomano D, Bruzziches R, Spera E, La Pera G, et al. (July 2009). "Effects of vardenafil administration on intravaginal ejaculatory latency time in men with lifelong premature ejaculation". International Journal of Impotence Research. 21 (4): 221–7.
doi:
10.1038/ijir.2009.21.
PMID19474796.
S2CID26078130.
^Kloner RA (December 2005). "Pharmacology and drug interaction effects of the phosphodiesterase 5 inhibitors: focus on alpha-blocker interactions". The American Journal of Cardiology. 96 (12B): 42M–46M.
doi:
10.1016/j.amjcard.2005.07.011.
PMID16387566.
^Carson CC (February 2006). "PDE5 inhibitors: are there differences?". The Canadian Journal of Urology. 13 (Suppl 1): 34–9.
PMID16526979.