Many medications can cause side effects. A side effect is an unwanted response to a medication when it is taken in normal doses. Side effects can be mild or severe, temporary or permanent.

The side effects listed below are not experienced by everyone who takes Videx Ec. If you are concerned about side effects, discuss the risks and benefits of Videx Ec with your doctor.

The following side effects have been reported by at least 1% of people taking Videx Ec. Many of these side effects can be managed, and some may go away on their own over time.

Contact your doctor if you experience these side effects and they are severe or bothersome. Your pharmacist may be able to advise you on managing side effects.

• Diarrhea
• dry eyes
• dryness of mouth
• gas
• headache
• heartburn
• loss of appetite
• nausea
• rash
• vomiting

Although most of the side effects listed below don't happen very often, they could lead to serious problems if you do not seek medical attention.

Check with your doctor as soon as possible if any of the following side effects occur:

• abdominal pain
• Fever and chills
• increased fat on the upper back, neck, breasts, and around the trunk; and loss of fat from the legs, arms, and face
• muscle aches
• signs of Anemia (low red blood cells; e.g., pale skin, unusual tiredness or weakness)
• signs of bleeding, e.g.:
• blood in stools
• blood in urine
• bloody nose
• coughing blood
• cuts that don't stop bleeding
• signs of Diabetes, e.g.:
• fruity smell to the breath
• increased thirst
• increased urination
• wounds that don't heal
• signs of infections, e.g.:
• fever or chills
• headache
• listlessness
• prolonged dizziness
• severe diarrhea
• shortness of breath
• stiff neck
• weight loss
• signs of liver problems, e.g.:
• dark urine
• diarrhea
• loss of appetite
• nausea
• pale stools
• vomiting
• weight loss
• yellowing of the skin or whites of the eyes
• tingling, burning, or numbness and pain in the hands or feet
• vision changes

Stop taking the medication and seek immediate medical attention if any of the following occur:

• signs of lactic acidosis, e.g.:
• abdominal pain
• dizziness
• increased breathing rate
• nausea
• rapid heart rate
• unusual tiredness
• vomiting
• signs of pancreatitis, e.g.:
• abdominal pain on the upper left side
• back pain
• chills
• fever
• nausea
• rapid heartbeat
• swollen abdomen
• signs of a serious allergic reaction, e.g.:
• abdominal cramps
• difficulty breathing
• nausea and vomiting
• swelling of the face and throat

Some people may experience side effects other than those listed. Check with your doctor if you notice any symptom that worries you while you are taking Videx Ec.

Videx® chewable tablets and pediatric solution are no longer available in Canada.

125 mg
Each white, opaque, enteric-coated beadlet capsule, printed in tan with "BMS 125 mg" and "6671", contains 125 mg of didanosine. Nonmedicinal ingredients: carboxymethylcellulose sodium, diethyl phthalate, methacrylic acid copolymer, sodium hydroxide, sodium starch glycolate, and talc; capsule shell: gelatin, sodium lauryl sulfate, and titanium dioxide. Capsules are imprinted with edible ink.

200 mg
Each white, opaque, enteric-coated beadlet capsule, printed in green with "BMS 200 mg" and "6672", contains 200 mg of didanosine. Nonmedicinal ingredients: carboxymethylcellulose sodium, diethyl phthalate, methacrylic acid copolymer, sodium hydroxide, sodium starch glycolate, and talc; capsule shell: gelatin, sodium lauryl sulfate, and titanium dioxide. Capsules are imprinted with edible ink.

250 mg
Each white, opaque, enteric-coated beadlet capsule, printed in blue with "BMS 250 mg" and "6673", contains 250 mg of didanosine. Nonmedicinal ingredients: carboxymethylcellulose sodium, diethyl phthalate, methacrylic acid copolymer, sodium hydroxide, sodium starch glycolate, and talc; capsule shell: gelatin, sodium lauryl sulfate, and titanium dioxide. Capsules are imprinted with edible ink.

400 mg
Each white, opaque, enteric-coated beadlet capsule, printed in red with "BMS 400 mg" and "6674", contains 400 mg of didanosine. Nonmedicinal ingredients: carboxymethylcellulose sodium, diethyl phthalate, methacrylic acid copolymer, sodium hydroxide, sodium starch glycolate, and talc; capsule shell: gelatin, sodium lauryl sulfate, and titanium dioxide. Capsules are imprinted with edible ink.

Do not take didanosine if you are allergic to didanosine or any ingredient of the medication.

There may be an interaction between didanosine and any of the following:

• alcohol
• Allopurinol
• atazanavir
• "azole" antifungals (e.g., fluconazole, itraconazole, ketoconazole)
• darunavir
• Febuxostat
• Ganciclovir
• Hydroxyurea
• indinavir
• lopinavir
• Methadone
• quinolone antibiotics (e.g., ciprofloxacin, moxifloxacin, Norfloxacin)
• ribavirin
• rilpivirine
• stavudine
• tenofovir
• tipranavir
• valganciclovir

If you are taking any of these medications, speak with your doctor or pharmacist. Depending on your specific circumstances, your doctor may want you to:

• stop taking one of the medications,
• change one of the medications to another,
• change how you are taking one or both of the medications, or
• leave everything as is.

An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.

Medications other than those listed above may interact with Videx Ec. Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications you are taking. Also tell them about any supplements you take. Since caffeine, alcohol, the Nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them.

Before you begin taking a medication, be sure to inform your doctor of any medical conditions or Allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should take Videx Ec.

Fat redistribution: Over time, Videx Ec may change how fat is distributed in your body and may change your body shape. You may notice increased fat in the upper back and neck, breast, around the back, chest, and stomach area; or loss of fat from the legs, arms, and face. The long-term effects of this are not known.

Immune reconstitution syndrome: Videx Ec may cause immune reconstitution syndrome, where signs and symptoms of inflammation from previous infections appear. These symptoms occur soon after starting anti-HIV medication and can vary. They are thought to occur as a result of the immune system improving and being able to fight infections that have been present without symptoms (such as pneumonia, herpes, or Tuberculosis). Report any new symptoms to your doctor as soon as possible.

Kidney function: Didanosine is removed from the body by the kidneys. Decreased kidney function may cause an increase in side effects due to an increased amount of medication in the body.

If you have reduced kidney function, discuss with your doctor how Videx Ec may affect your medical condition, how your medical condition may affect the dosing and effectiveness of Videx Ec, and whether any special monitoring is needed. People with severely reduced kidney function should not take Videx Ec.

Lactic acidosis and enlarged fatty liver: Didanosine can cause a rare but serious condition called lactic acidosis (build-up of lactic acid in the blood) together with an enlarged liver. This tends to occur more often in women, especially if they are overweight. If you experience any of the following symptoms, call your doctor immediately:

• abdominal pain, swelling, or bloating
• diarrhea
• fatigue
• feeling unwell
• nausea
• shortness of breath
• vomiting
• weakness
• weight loss

Your doctor will monitor your liver function periodically by ordering laboratory tests.

Liver function:  People with liver disease or reduced liver function appear to have an increased risk of additional liver damage due to taking didanosine. If you have liver disease or decreased liver function, discuss with your doctor how Videx Ec may affect your medical condition, how your medical condition may affect the dosing and effectiveness of Videx Ec, and whether any special monitoring is needed.

Liver failure has occurred in people taking didanosine who have had no previous liver problems. If you experience symptoms of liver problems (e.g., abdominal pain, persistent vomiting, feeling unwell, fever, itching, yellowing of the skin and eyes, dark urine), contact your doctor immediately.

Pancreatitis (inflammation of the pancreas): Didanosine may cause or worsen pancreatitis. If you have a history of or are at risk for developing pancreatitis, you should be closely monitored by your doctor while taking Videx Ec. If you develop signs of pancreatitis (e.g., upper left abdominal pain, back pain, nausea, fever, chills, rapid heartbeat, swollen abdomen), contact your doctor.

Peripheral Neuropathy: Didanosine may cause numbness, tingling or pain in the feet or hands. This is known as peripheral neuropathy, a nervous system complication of both the disease and Videx Ec. If you experience these symptoms, contact your doctor as soon as possible.

Portal hypertension: Portal hypertension (increased blood pressure in the large vein of the liver) may occur with normal use of didanosine. Your doctor will order blood tests to check for early signs of this complication. If you experience vomiting blood or an unusual increase in the size of your abdomen, contact your doctor as soon as possible.

Pregnancy: There have been reports of birth defects in babies born to mothers who took Videx Ec while pregnant. Videx Ec should not be used during pregnancy unless the benefits outweigh the risks. If you become pregnant while taking Videx Ec, contact your doctor immediately.

Breast-feeding: It is not known if didanosine passes into breast milk. Women who have HIV infection are cautioned against breast-feeding because of the risk of passing HIV to a baby who does not have the infection.

Children: The safety and effectiveness of Videx Ec have not been established for children.

Seniors: Seniors have an increased risk of side effects with didanosine. They may require lower doses and closer monitoring by the doctor.