It’s estimated that erectile dysfunction (ED) affects more than 18 million men in the United States alone.1 The majority of those men are over 40 years old, but it can strike no matter what your age. Sometimes ED is an unfortunate side effect of a disease. For instance, men who have diabetes, decreased testosterone levels, high blood pressure, an enlarged prostate, or some other health conditions may get ED. Often times after prostate surgery men experience ED due to nerve damage or other trauma to the male body.2 Sometimes smoking, alcohol use, or certain medications can all cause ED. It can even be the result of everyday pressures such as stress, anxiety, or just nervousness.3 Fortunately, no matter what the cause, Erectile Dysfunction can be successfully treated.4
While some men respond well to oral ED treatments such as Viagra or Cialis, others do not respond to these treatments or have uncomfortable or even dangerous side effects to these medications.5 In those cases custom compounded medications can often be used successfully to treat ED.6
The injectable medications Papaverine, Phentolamine, Alprostadil (Prostaglandin E1), and/or Atropine are used individually or in combination. While an injectable ED medication may sound intimidating or even painful, the truth is, the treatment involves very little discomfort and is an easy and very effective way to treat ED.7
Oral ED Medications
Viagra (Sildenafil) is available as an oral tablet ranging from 25 mg to 100 mg. A starting dose of 50 Mg taken about one hour prior to sexual intercourse has been recommended.8 Viagra has been reported as a safe and efficacious treatment for ED, however, it is ineffective in approximately 27 to 35% of the population and has been associated with a variety of adverse effects including headache, flushing, dyspepsia, and adverse interaction with nitrates and inhibitors of cytochrome P450 enzymes.9 Viagra should not be taken in conjunction with nitrate therapy.10
Cialis (Tadalafil) is available as an oral tablet ranging from 5 to 20 mg. The recommended tadalafil starting dose for most men is 10 mg, taken as needed before sexual activity (but not more than once daily). The dose may be increased to 20 mg or decreased to 5 mg, per its efficacy and the man’s personal tolerance of the drug.11 Cialis’s 36-hour effectiveness earned it the nickname, “The Weekend Pill”; like sildenafil, tadalafil is recommended as an ‘as needed’ medication. Cialis is the only one of the three that is also offered as a once-daily medication.
Orally Disintegrating Tablet (ODT)
An orally disintegrating tablet or orally dissolving tablet (ODT) differ from traditional tablets in that they are designed to be dissolved on the tongue rather than swallowed whole. An ODT is a solid dosage form that disintegrates and dissolves in the mouth (either on or beneath the tongue or in the buccal cavity) without water within 60 seconds or less.
Orally disintegrating tablets offer many of the advantages of solid and liquid dosage forms offer. ODTs present no risk of obstruction of the gastrointestinal tract, which is beneficial for patients who do not have access to water such as patients who are traveling. The rapid disintegration of the resulting tablets may result in a quick dissolution of the drug and fast absorption that can provide a rapid onset of action.12 The bioavailability of drugs that are absorbed in the mouth, pharynx, and esophagus may be increased13. Absorption of drugs before reaching the stomach avoids hepatic metabolism, which can reduce the dose and may increase the bioavailability of the drug.14 ODTs may have a faster onset of action and higher bioavailability occur via blood vessels under the tongue, rather than being absorbed through the digestive tract. Fast-acting dissolution provides dispersion before being swallowed, which may provide faster metabolism. ODTs may allow some of the active ingredient to be absorbed directly into the blood stream bypassing the patient’s hepatic system and first-pass metabolism.
Injectable ED Ingredients
Papaverine is particularly known as a smooth muscle relaxant and vasodilator. Its principle pharmacological action is as a non-specific vasdilator of the arterioles and capillaries.15 Major side-effects include priapism and corporal fibrosis. These side-effects are greatly reduced when papaverine is used in very low dosages and combined with phentolamine and alprostadil.
Phentolamine may provoke a reflex, increasing sympathetic outflow and the release of norepinephrine.16 When phentolamine is used for the treatment of ED, it is often used in combination with other agents (e.g. papaverine) to enhance its efficacy. The combination of phentolamine and papaverine for the treatment of ED has been studied extensively.1718 This combination can be efficacious and may induce erections sufficient for sexual intercourse in over 90% of cases.19
Prostaglandin E1 (Alprostadil) binds with PGE receptors, and the resultant relaxation response in the smooth muscle is mediated by cAMP.20 Little is known about the pharmacokinetics of PGE1 but it is believed that as much as 80% may be metabolized in one pass through the lungs.21 In all probability, this rapid degradation by the lungs accounts for its lack of any significant cardiovascular system side-effects when administered intracavernosally.22 It can also be metabolized in the penis.21 Alprostadil has also been used in combination with other agents, such as papaverine, and the combination was superior to only alprostadil.2324 Alprostadil is available as an intraurethral pellet (MUSE),25 intraurethral gel with penetration enhancers,26 or intracavernosal injection. Numerous studies show that the injection is more efficacious.27
Atropine is a non-selective muscarine agonist that functions by competitively binding to muscarine receptors, a class of acetylcholine receptor involved in the contraction and relaxation of smooth muscle and epithelial tissue throughout various parts of the body.28 These receptors, when activated locally in the penis by acetylcholine molecules, cause the corpus cavernosum to contract29 by inhibiting the absorption of acetylcholine by these receptors into cells in the vasculature of the penis, Atropine effectively relaxes the vessels in the penis and helps in achieving erection.30 While atropine’s efficacy when used alone is relatively insignificant and it’s use in combination with other injectables does not improve the success rates of a mixture without atropine, it can help reduce the pain30PGE1 can cause.31