PHENTOLAMINE (Intracavernosal)

Some commonly used brand names are:

In Canada?

• Rogitine

Generic name product may be available in the U.S. and Canada.

Category

• Erectile dysfunction therapy

Description

Phentolamine (fen-TOLE-a-meen) given by injectioncauses blood vessels to expand, thereby increasing blood flow. When injectedinto the penis (intracavernosal), it increases blood flow to the penis, whichresults in an erection.

This medicine should not be used as a sexual aid by men who do not haveerectile dysfunction. If the medicine is not used properly, permanent damageto the penis and loss of the ability to have erections could result.

Phentolamine is available only with your doctor's prescription, in thefollowing dosage form:

Parenteral
• Injection (U.S. and Canada)

Before Using This Medicine

In deciding to use a medicine,the risks of taking the medicine must be weighed against the good it willdo. This is a decision you and your doctor will make. For phentolamine, thefollowing should be considered:

Allergies?Tell your doctor if you have ever had any unusual orallergic reaction to phentolamine. Also tell your health care professionalif you are allergic to any other substances, such as foods, preservatives,or dyes.

Older adults?Many medicines have not been studied specificallyin older people. Therefore, it may not be known whether they work exactlythe same way they do in younger adults or if they cause different side effectsor problems in older people. Although there is no specific information comparingthe use of phentolamine for erectile dysfunction in the elderly, it is notexpected to cause different side effects or problems in older people thanit does in younger adults.

Other medicines?Although certain medicines should not be usedtogether at all, in other cases two different medicines may be used togethereven if an interaction might occur. In these cases, your doctor may want tochange the dose, or other precautions may be necessary. Tell your health careprofessional if you are taking any other prescription or nonprescription (over-the-counter[OTC]) medicine.

Other medical problems?The presence of other medicalproblems may affect the use of phentolamine. Make sure you tell your doctorif you have any other medical problems, especially:

• Bleeding problems?These conditions increase the risk of bleedingat the place of injection

• Priapism (history of) or
• Sickle cell disease?Patients with these conditions have anincreased risk of priapism (erection lasting longer than 4 hours) while using phentolamine

Proper Use of This Medicine

To give theinjection:

• Cleanse the injection site with alcohol. Using a sterile needle, inject the medicine slowly and directly into the baseof the penis as instructed by your doctor. It should not be injected justunder the skin. The injection is usually not painful, although youmay feel some tingling in the tip of your penis. If the injection is verypainful or you notice bruising or swelling at the place of injection, thatmeans you are injecting the medicine under the skin. Stop, withdraw the needle,and reposition it properly before continuing with the injection.
• After you have completed the injection, put pressure on the placeof injection to prevent bruising. Then massage your penis as instructed byyour doctor. This helps the medicine spread to all parts of the penis, sothat it will work better.

This medicine usually begins to work in about 10 minutes. You should attemptintercourse within 2 hours after injecting the medicine.

Dosing?The dose of phentolamine will be differentfor different patients. Follow your doctor's orders orthe directions on the label. The following information includes onlythe average doses of phentolamine. If your dose is different,do not change it unless your doctor tells you to do so.

• For injection dosage form:
  • For the treatment of impotence:
    • Adults? 0.5 to 1 milligram (mg) injected very slowly into thearea of your penis as directed by your doctor. Allow one or two minutes tocompletely inject the dose. Do not inject more than one dose in a day. Also,do not use this medicine more than two days in a row or more than three timesa week.

Storage?To store this medicine:

• Keep out of the reach of children.
• Store away from heat and direct light.
• Keep the medicine from freezing.

Precautions While Using This Medicine

Use the injection exactly as directed by your doctor.Do not use more of it and do not use it more often than ordered. If too muchis used, the erection may become so strong that it lasts too long and doesnot reverse when it should. This condition is called priapism, and it canbe very dangerous. If the effect is not reversed, the blood supply to thepenis may be cut off and permanent damage may occur.

Contact your doctor immediately if the erection lastsfor longer than 4 hours or if it becomes painful. This may be a signof priapism and must be treated right away to prevent permanent damage.

If you notice bleeding at the site when you inject the medicine, put pressureon the spot until the bleeding stops. If it doesn't stop, check with yourdoctor.

It is important for you to examine your penis regularly. Check with yourdoctor if you find a lump where the medicine has been injected or if you noticethat your penis is becoming curved. These may be signs that unwanted tissueis growing (called fibrosis), which should be seen by your doctor.

Side Effects of This Medicine

Along with its needed effects, a medicine may cause some unwanted effects.Although not all of these side effects may occur, if they do occur they mayneed medical attention.

Check with your doctorimmediately if the following side effects occur:

Rare

Erection continuing for more than 4 hours, or painful erection

Check with your doctor as soon as possible if the following side effectsoccur:

Rare

Dizziness; lumps in the penis

Other side effects may occur that usually do not need medical attention.These side effects may go away during treatment as your body adjusts to themedicine. However, check with your doctor if any of the following side effectscontinue or are bothersome:

Less common or rare

Bruising or bleeding at place of injection; burning (mild) along penis; difficulty in ejaculating; swelling at place of injection

Phentolamine injected into the penis may cause tingling at the tip ofthe penis. This is no cause for concern.

Other side effects not listed above may also occur insome patients. If you notice any other effects, check with your doctor.

Additional Information

Once a medicine has been approved for marketingfor a certain use, experience may show that it is also useful for other medicalproblems. Although this use is not included in product labeling, phentolamineis used in certain patients with the following medical conditions:

• Low doses of a three-drug combination of phentolamine, papaverine,and alprostadil as an injection may be used to treat erectile dysfunction.