Videx EC (Oral)

Didanosine is used together with other medicines to treat human immunodeficiency virus (HIV) infection. HIV is the virus that leads to acquired immune deficiency syndrome (AIDS).

Didanosine will not cure or prevent HIV infection or AIDS. It helps stop HIV from making copies of itself and seems to slow down the damage to the immune system. This may help postpone problems that are usually associated with AIDS or HIV disease. Didanosine will not stop you from passing HIV to others. People taking this medicine may still experience issues usually related to AIDS or HIV disease.

This medicine is available only with a prescription from your doctor.

The buffered tablets that you chew, crush, or mix with water are no longer available in the United States. This product was voluntarily discontinued and not due to safety issues. Didanosine delayed-release capsules (Videx® EC) and pediatric powder for oral solution are still available.

It is very important that your doctor check your or your child's progress at regular visits to ensure that this medicine is working correctly. Blood tests may be needed to look for unwanted effects.

Do not use didanosine if you or your child are also using allopurinol (Zyloprim®), ribavirin (Copegus®, Rebetol®), or stavudine (Zerit®). Using these medicines together may lead to serious side effects.

This medicine may cause a life-threatening condition called pancreatitis. Contact your doctor immediately if you or your child have more than one of these symptoms: bloating, chills, constipation, darkened urine, a fast heartbeat, fever, indigestion, loss of appetite, nausea, stomach pain, pain in the side or abdomen (which may radiate to the back), vomiting, or yellow eyes or skin.

Two rare but serious reactions to this medicine are lactic acidosis (too much acid in the blood) and liver toxicity, which includes an enlarged liver. These are more common if you are female, very overweight (obese), or have been taking anti-HIV medicines for a long time. Call your doctor right away if you or your child have more than one of these symptoms: abdominal or stomach discomfort or cramping, dark urine, decreased appetite, diarrhea, a general feeling of discomfort, light-colored stools, muscle cramping or pain, nausea, unusual tiredness or weakness, trouble breathing, vomiting, or yellow eyes or skin.

Contact your doctor immediately if you or your child have abdominal or stomach pain, black, tarry stools, bleeding gums, blood in the urine or stools, pinpoint red spots on the skin, or unusual bleeding or bruising. These may be symptoms of a condition called non-cirrhotic portal hypertension.

Tell your doctor right away if you or your child start having numbness, tingling, or burning pain in your hands, arms, legs, or feet. These may be symptoms of a condition called peripheral neuropathy.

Your immune system may become stronger when you start taking HIV medicines. Sometimes the immune system will begin to fight infections that were hidden in your body, such as pneumonia or tuberculosis, or may result in a flare-up of a hidden autoimmune disorder such as Graves' disease, polymyositis, or Guillain-Barré syndrome. Tell your doctor immediately if you notice any changes in your health.

This medicine may cause you or your child to lose fat from your legs, arms, or face. Discuss any concerns with your doctor.

Contact your doctor immediately if you or your child start seeing unusual colors or have blurred vision. Your doctor may want you to have regular eye checks by an eye doctor (ophthalmologist).

Do not drink alcohol while you are using this medicine.

This medicine will not prevent you from transmitting HIV to your partner during sex. Make sure you understand this and practice safe sex, even if your partner also has HIV, by using a latex condom or other barrier method. This medicine will also not stop you from transmitting HIV to others if they are exposed to your blood. Do not re-use or share needles with anyone.

Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal or vitamin supplements.

In deciding to use a medicine, you and your doctor must consider the risks of taking the medicine against the benefits it may provide. For this medicine, keep the following in mind:

Allergies

Inform your doctor if you have ever had any unusual or allergic reactions to this medicine or any other medicines. Also, tell your healthcare professional about any other allergies you may have, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.

Pediatric

Studies so far have not shown any specific problems in children aged 2 weeks and older that would limit the usefulness of didanosine.

Geriatric

Studies conducted thus far have not indicated any specific problems in elderly patients that would limit the usefulness of didanosine. However, older adults are more likely to have kidney issues related to aging, which may need caution and a dose adjustment for those taking didanosine.

Breast Feeding

There are no adequate studies in women to determine the risk to infants when using this medication during breastfeeding. Consider the potential benefits and risks before taking this medication while breastfeeding.

Interactions with Medicines

Some medicines should not be used together at all, while in other cases, two different medicines may be used together even if an interaction might happen. In these situations, your doctor may want to adjust the dose or take other precautions. It is especially important for your healthcare professional to know if you are taking any of the medicines listed below. The following interactions are based on their potential significance and are not necessarily a complete list.

Using this medicine with any of the following medicines is not recommended. Your doctor may decide not to treat you with this medication or change some of the other medicines you take.

• Allopurinol
• Oxypurinol
• Ribavirin
• Stavudine

Using this medicine with any of the following medicines is usually not recommended, but may be necessary in some cases. If both medicines are prescribed together, your doctor may adjust the dose or frequency of one or both medicines.

• Atazanavir
• Cabotegravir
• Darunavir
• Hydroxyurea
• Orlistat
• Tacrolimus
• Tenofovir Disoproxil Fumarate
• Zalcitabine

Using this medicine with any of the following medicines may increase the risk of certain side effects, but taking both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may adjust the dose or frequency of one or both medicines.

• Atevirdine
• Ciprofloxacin
• Delavirdine
• Enoxacin
• Ganciclovir
• Indinavir
• Itraconazole
• Ketoconazole
• Lomefloxacin
• Methadone
• Metoclopramide
• Moxifloxacin
• Nelfinavir
• Nirmatrelvir
• Norfloxacin
• Ofloxacin
• Ranitidine
• Rifabutin
• Ritonavir
• Sulfamethoxazole
• Trimethoprim
• Trovafloxacin Mesylate
• Valganciclovir

Interactions with Food/Tobacco/Alcohol

Some medicines should not be taken around mealtime or with certain types of food due to potential interactions. Using alcohol or tobacco with some medicines may also lead to interactions. The following interactions are based on their potential significance and are not necessarily a complete list.

Other Medical Problems

Having other medical issues may affect how this medicine works. Be sure to inform your doctor if you have any other medical problems, especially:

• Alcohol use, either current or past
• Liver disease (including hepatitis)
• Obesity (overweight)
• History of pancreatitis (inflammation of the pancreas)
• History of peripheral neuropathy (nerve disorder)—Use with caution. May worsen side effects.

• Kidney disease—Use with caution. The effects may be stronger due to slower removal of the medicine from the body.

• Portal hypertension (high blood pressure in the portal vein of the liver)—Use with caution. May worsen this condition.

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 may need medical attention.

Check with your doctor immediately if any of the following side effects occur:

Less common

• Nausea
• stomach pain
• tingling, burning, numbness, and pain in the hands or feet
• vomiting

Rare

• Chills
• fever
• itching, skin rash
• seizures
• sore throat
• swelling of the feet or lower legs
• unusual bleeding and bruising
• unusual tiredness and weakness
• yellow skin and eyes

Incidence not known

• Anxiety
• black, tarry stools
• bleeding gums
• blindness
• bloating
• blood in the urine or stools
• blue-yellow color blindness
• blurred vision
• change in the color of the eye
• chest pain
• clay colored stools
• cold sweats
• confusion
• constipation
• cool, pale skin
• cough
• dark urine
• decreased appetite
• decreased vision
• depression
• diarrhea
• difficulty with moving
• difficulty with swallowing
• dizziness
• dry eyes or mouth
• eye pain
• fast heartbeat
• fast, shallow breathing
• flushed, dry skin
• fruit-like breath odor
• general feeling of discomfort
• headache
• hives
• increased hunger
• increased thirst
• increased urination
• indigestion
• joint pain
• light-colored stools
• loss of appetite
• loss of consciousness
• muscle aching, cramping, or pain
• nightmares
• painful or difficult urination
• pains in the stomach, side, or abdomen, possibly radiating to the back
• pinpoint red spots on the skin
• puffiness or swelling of the eyelids or around the eyes, face, lips, or tongue
• right upper abdominal or stomach pain and fullness
• shakiness
• sleepiness
• slurred speech
• sores, ulcers, or white spots on the lips or in the mouth
• stomach ache or discomfort
• sweating
• swollen glands or joints
• tightness in the chest
• troubled breathing with exertion
• unexplained weight loss
• unsteadiness or awkwardness
• weakness in the arms, hands, legs, or feet

Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More common

• Difficulty with sleeping
• irritability
• restlessness

Incidence not known

• Belching
• excess air or gas in the stomach or bowels
• feeling of fullness
• hair loss or thinning of the hair
• heartburn
• indigestion
• lack or loss of strength
• passing gas

Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.

Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.

In the U.S.

• Videx
• Videx EC
• Videx Pediatric

Available Dosage Forms:

• Capsule, Delayed Release

Therapeutic Class: Antiretroviral Agent

Pharmacologic Class: Nucleoside Reverse Transcriptase Inhibitor

Take this medicine exactly as directed by your doctor. Do not take more of it, do not take it more often, and do not take it for a longer time than your doctor ordered. Also, do not stop taking this medicine without checking first with your doctor.

This medicine comes with a Medication Guide. Read and follow these instructions carefully. Ask your doctor if you have any questions.

Keep taking didanosine for the full time of treatment, even if you begin to feel better. Only take medicine that your doctor has prescribed specifically for you. Do not share your medicine with other people.

This medicine works best when there is a constant amount in the blood. To help keep the amount constant, do not miss any doses. If you need help in planning the best times to take your medicine, check with your doctor.

Didanosine should be taken on an empty stomach since food may keep it from working properly. Didanosine oral liquid should be taken at least 30 minutes before or 2 hours after you eat.

Swallow the delayed-release capsule whole. Do not break, crush, chew, or open it.

Shake the oral liquid before use. Measure each dose with a specially marked measuring spoon or measuring cup. The average household teaspoon may not hold the right amount of liquid.

Dosing

The dose of this medicine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

• For HIV infection: For oral dosage form (delayed-release capsules): Adults and children who can swallow capsules—Dose is based on body weight and must be determined by your doctor. For patients weighing 60 kilograms (kg) or more—400 milligrams (mg) once a day. For patients weighing 25 kg to less than 60 kg—250 mg once a day. For patients weighing 20 kg to less than 25 kg—200 mg once a day. Children weighing less than 20 kg—The oral capsules are not given to small children. For oral dosage form (solution): Adults weighing 60 kilograms (kg) or more—Dose is based on body weight and must be determined by your doctor. The usual dose is 200 milligrams (mg) 2 times a day or 400 mg once a day. Adults weighing less than 60 kg—Dose is based on body weight and must be determined by your doctor. The usual dose is 125 mg 2 times a day or 250 mg once a day. Children older than 8 months of age—Dose is based on body size and must be determined by your doctor. The usual dose is 120 milligrams per square meter (mg/m(2)) 2 times a day. Infants 2 weeks to 8 months old—Dose is based on body size and must be determined by your doctor. The usual dose is 100 mg/m(2) 2 times a day. Infants younger than 2 weeks old—Use and dose must be determined by your doctor.

Missed Dose

If you miss a dose of this medicine, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.

Storage

Keep out of the reach of children.

Do not keep outdated medicine or medicine no longer needed.

Ask your healthcare professional how you should dispose of any medicine you do not use.

Store the delayed-release capsules in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.

Store the oral liquid in the refrigerator. Throw away any unused medicine after 30 days.