The phosphodiesterase – 5 enzyme (PDE-5) is found all over the human body and especially within the penis, pulmonary blood vessels, smooth muscles, and platelets. It is involved in various physiological processes such as smooth muscle contraction and relaxation. PDE-5 has the largest distribution in the penile corpus cavernosum. Since tadalafil is a competitive PDE-5 antagonist, it is able to work similarly to sildenafil and vardenafil to relax muscles and increase blood flow thereby producing an erection in men.1 It also acts on PDE-5 in the pulmonary vasculature causing the blood vessels to relax and widen to decrease mean pulmonary artery pressure.2 Tadalafil is also known to reduce symptoms of benign prostatic hyperplasia (BPH), however its mechanism has not been established.3
Tadalafil is commonly administered orally. The duration of action of tadalafil for the treatment of erectile dysfunction is up to 36 hours (longer than that of sildenafil and vardenafil). Tadalafil has no effect in the absence of sexual stimulation. Because PDE inhibitors promote erection only in the presence of sexual stimulation, the longer duration of action of tadalafil allows for more spontaneity in sexual activity.1
Unlike sildenafil, visual disturbances have not been reported with tadalafil.1 Since tadalafil can inhibit PDE5 on esophageal smooth muscle, this can cause reduced esophageal motility and lower esophageal sphincter (LES) tone, which can worsen the symptoms of gastroesophageal reflux disease (GERD).
Tadalafil is administered orally for the treatment of male erectile dysfunction (ED), pulmonary arterial hypertension (PAH), and benign prostatic hypertrophy (BPH).
Commercially-Available Tadalafil Options
Tadalafil was FDA approved for use in treating erectile dysfunction in 1998. Today, it is available commercially as an oral tablet in various strengths (2.5 mg, 5 mg, 10 mg, and 20 mg).
Compounded Tadalafil Options
Since tadalafil is already commercially available as an oral tablet, compounded tadalafil oral disintegrating tablets (ODT) are reserved for patients that require a higher or more customizable dosage than what is available commercially and for those that would benefit from an oral disintegrating formulation as determined by a prescriber. The most popular formulation compounded at Galleria Medical Pharmacy is tadalafil 25 mg ODT. An oral disintegrating tablet is similar to a hard tablet taken orally but is designed to quickly disintegrate in the mouth. It may also be placed under the tongue for a potential faster onset of action and to reduce upset stomach sometimes experienced with oral tablets. ODTs are quad-scored and can be broken into smaller dosage forms if necessary.
Store this medication at 68°F to 77°F (20°C to 25°C) and away from heat, moisture and light. Keep all medicine out of the reach of children. Throw away any unused medicine after the beyond use date. Do not flush unused medications or pour down a sink or drain.
- Montague DK, Jarow JP, Broderick GA, et al. Chapter 1: The management of erectile dysfunction: an AUA update. J Urol 2005;174:230-9.
- Adcirca (tadalafil) package insert. Indianapolis, IN: Lilly ICOS, LLC; 2011 Apr.
- Cialis (tadalafil) package insert. Indianapolis, IN: Lilly ICOS, LLC; 2011 Oct.
Compounding Pharmacy Statement
Tadalafil ODTs are compounded with drug components whose suppliers are registered with the FDA. While Galleria Medical Pharmacy adheres to USP <795> guidelines and applicable state and federal regulations to meet the required quality standards, the statements made regarding compounded tadalafil ODTs have not been evaluated by the FDA for safety or clinical effectiveness. As such, this preparation is not intended to diagnose, treat, cure, or prevent any disease. For inquiries concerning this preparation, please contact (504) 267-9876.