DIDANOSINE (VIDEX, VIDEX EC, ddl) USE: Didanosine is an antiviral treatment in a class of drugs called nucleoside reverse transcriptase inhibitors (NRTI). This medication is used in combination with other medications to treat people with HIV (human immunodeficiency virus) infection. This medication is not a cure for HIV or AIDS (acquired immune deficiency syndrome) but may slow the progress of the disease if used correctly. AVAILABLE AS: Videx chew/dispersible buffered tablet in 25, 50, 100, 150, and 200 milligrams (mg). Videx buffered powder for oral solution in packets of 100, 167, and 250 mg. Videx pediatric pwdr for oral solution in 4 and 8 ounce bottles of 2 or 4 grams respectively (10mg/ml). Videx EC delayed-release caps in 125, 200, 250 and 400 mg HOW TO USE THIS MEDICATION: It is important to use this medication exactly as directed by your doctor. Do not stop taking your medication without consulting your physician first. Didanosine comes in various dosage forms including a delayed release capsule, chewable tablets, powder and oral liquids. All forms of the medication should be taken on an empty stomach at least an hour before or two hours after meals. The delayed-release capsules should be taken only once a day and swallowed whole. Do not crush, chew, break or open these capsules. Chew the chewable tablets before swallowing them. These tablets can be dissolved in one ounce of water (2 tablespoons) and must be consumed right away. Two tablespoons of clear apple juice may be added to the water to add flavor. Do not add any other types of liquid. Drink this solution right away to maintain stability. Mix the powder with four ounces (half a glass) of water. Stir this mixture until it is completely dissolved and drink it right away. Other liquids including apple juice may not be added to this product. The oral liquid should be measured with a measuring device to obtain the most accurate dose. This product must be shaken every time before use and kept in the refrigerator. Do not freeze. After 30 days the liquid form of this medication must be thrown away. Store your medication (other than the liquid) in a cool, dry place away from excessive heat, cold, light or moisture. Keep medication out of the reach of children. It is very important to take every dose of your medication in order for it to work correctly. If you do miss a dose of didanosine, take it as soon as you remember unless it is close to your next dose. Do not take two doses at once. If you think you may have taken too much of your medication, contact your local poison control center or emergency room right away. CONTRAINDICATIONS: Do not use didanosine if you are allergic to didanosine or any of its components. SIDE EFFECTS: Common side effects that most likely will go away with time include headache, mild nausea, vomiting, upset stomach, diarrhea, or decreased appetite, and dryness of the mouth or eyes. Other side effects you should talk to your doctor about include a rash or
redistribution of body fat. This may include increased fat around the upper neck and back, breasts, trunk and abdomen. Loss of fat from the arms, legs and face may also occur. Talk to your doctor about ways to manage these side effects with diet, exercise or medications. Warning: Contact you doctor immediately if you experience any of the conditions listed below. Stop taking didanosine and seek medical attention immediately if you experience an allergic reaction (difficulty breathing; closing of the throat; swelling of the lips, tongue or face; or hives). Pancreatitis (inflammation of the pancreas) is also a severe side effect that may include symptoms of nausea, vomiting, diarrhea, and abdominal pain. This condition can be aggravated by alcohol use and therefore should be avoided. Signs of a severe condition called peripheral neuropathy (nerve damage) include numbness, loss of feeling, or tingling or pain in the hands or feet. Lactic acidosis or liver disease is also a rare but serious side effect of didanosine. Symptoms of this may include yellowing of the skin or eyes, nausea, vomiting, shortness of breath, weakness, abdominal pain or discomfort, bloating, tenderness, unusual bleeding or bruising, or severe fatigue. Other serious side effects include fever, chills, visual changes (decreased vision, blindness, eye pain, or changes in eye color), or suddenly slow or irregular heartbeat. Notify your doctor if you currently have or have had any of the following conditions in the past: phenylketonuria (PKU), gout, pancreas problems, or kidney or liver disease. Also report any past or present nerve problems or medications that you are taking that may affect your nerves. Notify your doctor if you are pregnant, planning to become pregnant or breastfeeding. Didanosine’s effects on an unborn baby are still unclear. People with HIV should never breastfeed because of the risk of transmitting HIV to the infant. This medication does not prevent the transmission of HIV to other people. Make sure you understand and practice safe sex and do not share needles with anyone. DRUG INTERACTIONS: Most formulations of didanosine have an antacid to protect the drug from the acidic environment of your stomach. Therefore additional antacids should be separated from your dose of didanosine by at least two hours. The buffered form of didanosine can change the effectiveness of certain antibiotics which should not be taken within two to four hours of taking didnosine. Separate the following drugs from didanosine by at lease two to four hours: tetracycline (Sumycin, Terramycin), doxycycline (Doryx, Vibramycin), minocycline (Minocin), Ciprofloxacin (Cipro), enoxacin (Penetrex), gatifloxacin (Tequin), levofloxacin (Levaquin), lomefloxacin (Maxaquin), moxifloxacin (Avelox), ofloxacin (Floxin), sparfloxacin (Zagam), trovafloxacin (Trovan), and norfloxacin (Noroxin). It is recommended that didanosine be used in combination with other anti-HIV medication. However, some of these medications may change how didanosine works in your body and may need the dose to be adjusted or should be separated from your dose of didanosine. These include indinavir (Crixivan), delavirdine (Rescriptor), nelfinavir (Viracept), ritonavir (Norvir), and tenofovir (Viread). Certain antifungal medication need to be given in an acidic environment and should be avoided or separated from you didanosine dose by at least two hours. These include ketoconazole (Nizoral) and itraconazole (Sporanox). Other medications to avoid include allopurinol (Zyloprim), methadone and ribavirin (Rebetol, Rebetron). Ask your doctor or pharmacist about any medications including over the counter, herbal, vitamin, and prescription products before using them with didanosine. References: see references 16-20
Le reazioni indesiderate da farmaci Tutti noi impieghiamo farmaci per curare le patologie acute o croniche che ci affliggono o per alleviare sintomi sgradevoli che si presentano in diverse occasioni. Tuttavia è importante ricordare che i farmaci, oltre agli effetti benefici documentati ed attesi che posseggono, causano effetti generalmente definiti come secondari e causati dalla int