Erectile dysfunction (ED)
The inability to achieve or maintain penile erection long enough for sexual activity.
affects men primarily between the ages of 40 and 70.
About 20 million men in the United States suffer from this condition, and this number is projected to increase to greater than 300 million by the year 2025
The standard first-line treatment for this condition is oral phosphodiesterase type 5 (PDE5) inhibitors such as Sildenafil and Tadalafil; these work by relaxing of the corpus cavernosum inside the penis and consequently, penile erection 
Some individuals, however, who may not tolerate PDE5 inhibitors for any reasons or are poorly responsive to this class of medications. An alternative option that has been used with promising results in the management of ED is TriMix. TriMix is a second-line medication used to treat ED in men for whom PDE5 inhibitors are not an acceptable option.
Components of TriMix
TriMix contains a mixture of three drugs: phentolamine, papaverine and alprostadil.
This drug is not readily available in traditional retail pharmacies but must be specially made at compounding pharmacies. The components of TriMix work synergistically causing sustained penile erections in individuals suffering from ED.
In contrast to the first-line drug treatment of ED, PDE5 inhibitors, which are administered orally, TriMix is an injectable medication which is administered locally into the penis.
This medication is typically compounded at dosages that are tailored to the requirements of everyone.
How does TriMix work?
Injecting Trimix to the corpus cavernosum, results in the relaxation, expansion, and filling of the corpus cavernosum with blood. This may result in penile erections that lasts throughout the duration of sexual intercourse.
There are two primary reasons that men with ED may consider using TriMix:
1) Failed treatment with first-line therapy such as PDE5 inhibitors.
2) Hypersensitivity or other reactions to PDE5 inhibitors.
Injectable TriMix has been shown to be efficacious in the management of ED. Studies have indicated that TriMix has an approximate overall success rate of 80 – 90 percent 
- Mild to moderate pain during injection
- Painful sensation with erection
- Small amount of bleeding at the injection site.
- Call your healthcare provider if you notice any redness, lumps, swelling, tenderness, or curvature of the erect penis. The prescribing physician should be consulted immediately if the erection becomes prolonged.
Precautions and Contraindications
Do not take this medicine with any of the following Conditions:
- Hypersensitivity or allergy to any component of this formulation.
- Conditions predisposing you to priapism (painful erection lasting 4 hours or more)
- Sickle cell anemia
- Multiple myeloma or leukemia
- Anatomical deformation of the penis or penile implants
- Direction by your physician that sexual activity is inadvisable or contraindicated.
Store refrigerated or frozen as directed, protect from 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.
How to Self-Administer
Some men may feel anxious or squeamish about self-injecting themselves, this is a relatively painless procedure if done properly with correct technique. Discussed below are the steps that are needed to safely self-administer the TriMix injection 
- Wash hands thoroughly with soap and water or an alcohol-based solution to maintain proper hygiene.
- Wipe the top of the rubber stopper thoroughly with an alcohol pad.
- Insert a syringe into the vial through the rubber stopper and draw out the prescribed amount of TriMix into the syringe. Ensure that there are no air bubbles by tapping the syringe.
- Find an injection site on the penis. Do not inject at the top or the bottom of the penis. Also avoid injecting directly into any visible veins or arteries on the penis, as well as along the midline. The optimal locations to administer the TriMix injection are at the sides of the penis. Avoid using the same spot repeatedly for injections as this may result in the scarring of penile tissue.
- Once an injection site has been found, thoroughly wipe it with a fresh alcohol swab.
- Insert the needle into the penis and slowly depress the plunger to release the TriMix medication into the corpora cavernosa of the penis. Remove and carefully dispose of the syringe when this completed.
- Apply pressure to the injection site and massage the penis to ensure thorough distribution of the medication throughout the tissues inside the penis.
The effects of TriMix become evident about 5 – 15 minutes after its injection into the penis as it induces a penile erection. Its duration action typically varies depending on the individual, ranging anywhere between half an hour to an hour. However, its effects should not last longer than 3 hours.
The prescribing physician should be consulted immediately if the erection becomes prolonged.
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