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Common Name:
delavirdine (DLV)
Brand Name:
Rescriptor |
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Class: non-nucleoside analog (also called non-nucleoside reverse transcriptase inhibitor, NNRTI or non-nuke)
Standard dose: Two 200 mg tablets or four 100 mg tablets three times a day (every 8 hours). Only the 100 mg tablets can be dissolved in liquid, however avoid grapefruit juice; no food restrictions (may be taken with or without food). Take missed dose as soon as possible, but do not double up on your next dose.
AWP: $303.70 / month for 200 mg
Manufacturer contact: Pharmacia and Upjohn Company, a Pfizer company, www.pfizer.com, 1-800-879-3477 (TRY-FIRST)
AIDSInfo:
1 (800) HIV–0440 (448–0440), www.aidsinfo.nih.gov
Potential side effects and toxicity: Most common side effects include headache, nausea, vomiting, diarrhea, fatigue, elevated liver enzymes, itchy skin or rash. A serious side effect of the NNRTI class is rash, which can be life-threatening. Most rashes occur within the first 1–3 weeks after starting Rescriptor. If you experience blistering, mouth lesions, conjunctivitis (redness or inflammation of eye, which if untreated may result in permanent vision loss), swelling, muscle or joint aches, fever or general malaise (general ill feeling), you may need to stop the medications so seek medical attention immediately. Body fat accumulation or redistribution may occur.
Potential drug interactions: You cannot take Rescriptor with Versed (midazolam), Halcion (triazolam) and Xanax (alprazolam), Orap (pimozide), ergot alkaloids, used for migraine headaches (Wigraine, Methergine, and Cafergot) in any form, or the herb St. John’s wort. Do not use Zocor (simvastatin), Vytorin, or Mevacor (lovastatin) cholesterol (lipid) lowering meds; suggested alternatives are Lipitor (atorvastatin), Lescol (fluvastatin), Crestor (rosuvastatin), and Pravachol (pravastatin, the one with less frequency of problems and interactions according to study data). Liver enzymes should be checked regularly if you are on these cholesterol meds, as they can increase risk for liver toxicity with Rescriptor. Certain amphetamines and antiarrhythmic drugs should not be used with Rescriptor, therefore inform your healthcare provider if you have a history of heart or blood pressure problems. Potential toxicity when given with Biaxin (clarithromycin), dapsone, Mycobutin (rifabutin), Procardia or Adalat (nifedipine), Norvasc (amlodipine), Plendil (felodipine), Coumadin (warfarin), and quinidine. Tegretol (carbamazepine, an anti-seizure medication used to treat peripheral neuropathy), phenobarbital, and Dilantin (phenytoin). Mycobutin, and rifampin (used to treat tuberculosis) are drugs that decrease Rescriptor levels. Rescriptor is not recommended with either rifampin or Mycobutin. Rescriptor increases levels of Crixivan, Lexiva, Invirase, Kaletra, Norvir, Reyataz, Viracept, immunosuppressants, birth control pills (ethinyl estradiol), and methadone, so caution is advised if using together. Cialis, Levitra, and Viagra levels are increased by Rescriptor; doses should not exceed 10 mg Cialis per 72 hours, 2.5 mg Levitra per 24 hours, or 25 mg Viagra per 48 hours. Also, increased levels of trazodone (Desyrel) can occur with Rescriptor. A lower dose of trazodone is recommended. Increased levels of the inhaled and nasal sprays that contain fluticasone, a steroid for asthma or allergies (found in Advair, Flonase, and Flovent) can occur with Rescriptor and therefore should be used with caution.
Tips: Research demonstrates smaller doses of Rescriptor increase blood levels of some protease inhibitors, making it unique among the NNRTIs. Some people who cannot tolerate Norvir (ritonavir) are successfully using Rescriptor instead to boost their protease inhibitor. Studies of this use, however, have not been published. Antacids (like Tagamet, Zantac, Prilosec, and Tums) and gastric achlorhydria (low stomach acid) decrease absorption of Rescriptor, so take at least one hour apart from these drugs and take with acidic beverages such as orange or cranberry juice. Please see package insert for more complete potential side effects and interactions.
Rescriptor is rarely used these days. It’s dosed three times a day, hasn’t been as extensively studied as Sustiva or Viramune, and may be less effective. There are some people with unusual NNRTI mutations that cause resistance to Sustiva and Viramune but not to Rescriptor. No one has ever studied using Rescriptor for that purpose, but I have one patient who’s taking it because of her funny resistance mutations, and she’s doing great. For her sake, I hope the drug sticks around.—Joel Gallant, M.D.
Rescriptor, which is so uncommonly used that almost no one remembers its generic name (I don’t), is from the small class of drugs known as non-nucleoside RT inhibitors. It never achieved the success of the others in this class, Sustiva and Viramune. This is due to the fact that it is more difficult to use because it takes more pills to achieve the dose, generally lower efficacy and generally higher side effects. So why is it still available? Hard to say. The drug was part of a package deal that came to Pfizer when it purchased a smaller drug company. There are some physicians who use Rescriptor as a booster for indinavir, another drug that is not widely used. Indinavir requires some kind of booster and the choices are either Norvir or Rescriptor. Docs who passionately dislike Norvir, and use indinavir, sometimes boost it with Rescriptor. Given all the other well proven drugs available today, the logic of this approach escapes most people.—Martin Delaney
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