Didanosine

Brand names

• Videx

Usage

To treat HIV infection. While not a cure for HIV, this medicament may suppress the replication of the virus and delay the progression of the disease.

How it works

Didanosine (also known as dideoxyinosine or ddl) interferes with the activity of enzymes needed for the replication of DNA in viral cells.

Side effects

Serious

Nerve damage causing numbness, tingling, prickling, or pain in the hands and feet; pancreatitis (inflammation of the pancreas) causing abdominal pain, nausea, and vomiting.

Common

Temporary toxicity of the central nervous system causing headache, anxiety, irritability, restlessness, or sleep disruption; gastrointestinal disturbances, including stomach pain, gas, nausea, vomiting, and diarrhea; dry mouth.

Less common

Swollen hands or legs, shortness of breath, yellow discoloration of the eyes or skin, rash, itch, weakness, vision problems, muscle aches or spasms, muscle wasting, pain, pneumonia, cough, hair loss.

Possible interactions

Other medicaments:

Didanosine may increase the effects of:

• zidovudine (Retrovir) and enhance its antiviral effect against HIV.

Didanosine may decrease the effects of:



• ciprofloxacin (Cipro) and other fluoroquinolones, if taken at the same time; take ciprofloxacin at least 2 hours before taking didanosine.
• dapsone and render it ineffective; avoid concurrent use.
• indinavir (Crixivan) and blunt therapeutic benefits; separate dosing by 2 hours.
• itraconazole (Sporanox). Separate dosing by at least 2 hours.
• ketoconazole (Nizoral), if taken at the same time; take ketoconazole at least 2 hours before taking didanosine.
• tetracyclines, if taken at the same time; take tetracyclines at least 2 hours before taking didanosine.

  Didanosine taken concurrently with:
  
  

• allopurinol (various) increased didanosine absorption in two patients with damaged kidneys. Caution and blood levels are prudent if this medicine is used in patients with kidney failure.
• amprenavir (Agenerase) will probably decrease amprenavir absorption. Separate doses by at least one hour.
• antacids will decrease didanosine absorption and lower its therapeutic benefit.
• delavirdine (Rescriptor) may lower both medicament levels. Separate doses by an hour.
• fluconazole (Diflucan) and other azole antifungals may decrease fluconazole benefits.
• histamine (H2) blocking medicaments - cimetidine, etc.-may increase didanosine toxicity.
• pentamidine or sulfamethoxazole may increase the risk of medicament-induced pancreatitis; watch for significant symptoms.
• ritonavir (Norvir) will inactivate both medicines. Separate doses by two and a half to three hours.
• triazolam (Halcion) may cause confusion.
• zalcitabine (Hivid) may cause increased neurotoxicity.

Herbal medicines or minerals:

Echinacea: some patients use Echinacea to attempt to boost their immune systems. Unfortunately, use of Echinacea is not recommended in people with damaged immune systems. This herb may also actually weaken any immune system if it is used too often or for too long a time.

Beverages:

Do not take with acidic fruit juices.

Discontinuation:

Do not stop this medicament without your physician's knowledge and guidance.