Method of Delivery

• Caverject and TriMix are delivered in extremely different ways. Caverject is delivered as a small injection directly to the side of the penis. It uses an IMPULSE pen to carry and mix the injected solution, and disposable needles to inject it. TriMix comes in a gel platform and is applied with the aid of the ED-gel Easy Applicator, which measures each dose for the user and mixes the TriMix solution at the time of application. It is rubbed directly onto the penis at the recommended dose. TriMix was originally released as an injectable solution, but the gel form is predominantly how it is prescribed today.
  
  

Ingredients and How They Work

• Unlike common ED drugs such as Cialis or Viagra, which affect the central nervous system, Caverject and TriMix work directly on the tissues in the penis. Caverject's active ingredient is alprostadil; upon injection, it causes the blood vessels in the penis to expand, increasing blood flow and ultimately resulting in an erection in most users. TriMix gel is a mixture of three active ingredients that are absorbed through the skin: papaverine, prostaglandin E1 and phentolamine. These ingredients increase levels of specific chemicals in the penis, which in turn leads to an expansion and entrapment of blood in those chambers, causing an erection.
  
  

Precautions

• When using Caverject, the needle is incredibly fine (29 gauge), and it is possible it can be broken if used roughly or improperly, so special care should be taken when injecting the solution into the penis. Being a topical gel, TriMix doesn't have that problem. Both TriMix and Caverject carry a warning that they should not be used more than once every 24 hours, and not more than three times in a week, or else incidence of fibrosis (scarification and curvature of the penis) rises.
  
  

Side Effects

• Side effects of Caverject include localized pain at the injection site, as well as localized reactions indicative of an allergic response. In some patients, curvature of the penis was a reported side effect, along with lumps. Reported side effects of TriMix include localized reactions (usually an allergic reaction), minor bleeding or pain on the penis or groin area, as well as more systemic symptoms such as heart palpitations, dizziness or symptoms that mimic the flu. Both drugs carry a warning against priapism, which occurs in individuals who have an erection lasting longer than four hours. This can lead to serious side effects, including loss of the penis.
  
  

Cost

• One limiting factor for both TriMix and Caverject is a relatively high price range, and it is thus generally used when systemic treatment with PDE5 inhibitors (such as Viagra and Cialis) fails or when the side effects are not well-tolerated. The price of TriMix generally ranges from $130 to $140 for a six-dose cycle, and Caverject is more expensive, usually well over $200 for the same number of treatments. These prices can vary widely, depending on numerous factors, including location and insurance coverage.