Drugs: Look-Alike Names Lead to Drug Mix-Ups

The Wall Street Journal
Rochelle Sharpe

WASHINGTON – Drug names can be hazardous to your health – and to pharmaceutical companies, too.

Recently three drug addicts who needed Narcan to increase dangerously slow breathing rates mistakenly received Norcuron, a muscle relaxant that can stop breathing, according to the Institute for Safe Medication Practices, a nonprofit group based in Warminster, Pa., that tracks medication errors. Two patients stopped breathing and another went into cardiac and respiratory arrest, says Michael Cohen, who heads the institute. His group first recorded a Narcan/Norcuron mix-up in 1993.

Naming drugs isn’t just a creative endeavor any more. It has become a public-health issue, drawing attention from the Food and Drug Administration, the pharmaceutical industry and safety advocates.

Medication errors now cause roughly one death each day, and name confusion causes about one-fourth of all medication errors, says Jerry Phillips, the head of the FDA’s labeling division. The potential for name mix-ups is also getting worse, with more new drugs being approved more quickly than ever before, creating a huge influx of unfamiliar names. Drugstore consolidation and staff reductions exacerbate the problem, pharmacists say.

In November 1997, the FDA, which had been reviewing drug names informally since 1989, started requiring drug companies to clear proposed names with the agency. This past January, at a conference on minimizing medication errors, it pushed for new ways to avoid name confusion. Among the suggestions: testing names in real-world situations and using questionnaires and computers to search for similar names more systematically.

Meanwhile an informal network of pharmacists and nonprofit groups is doing what it can to prevent errors. Earlier this month, Donald Sullivan, a professor at Ohio Northern University College of Pharmacy, noticed that G.D. Searle & Co.’s proposed breakthrough arthritis drug, Celebra, sounded dangerously similar to Celexa, Forest Laboratories’ antidepressant, which went on the market this past July.

Alerted by the pharmacist, the FDA ordered Searle, a unit of Monsanto Co., to come up with a new name. Searle’s choice: Celebrex. The company kept the name relatively similar because a lot of people were already familiar with the old name, a spokeswoman says.

Or consider Prilosec, the biggest selling drug in the country. Merck & Co. originally called the anti-ulcer medication Losec, but pharmacists complained that name sounded too much like Lasix, a diuretic made by Hoechst Marion Roussel, a unit of Hoechst AG.

In 1990, after the drugs were mixed up and a patient died, Merck changed the name to Prilosec at a cost of millions of dollars. But since then, written prescriptions for the drug have gotten confused with orders for Prozac more than a dozen times.

With so many drug trademarks on the market, “the best you can hope for when you change a name is that you won’t go from bad to worse,” says George Di Domizio, who headed Merck’s trademark committee during the Losec debacle and now works as a drug-name consultant.

To try to reduce errors, the Institute for Safe Medication Practices calls attention to mix-ups in its twice-monthly newsletter, which is distributed to 5,700 hospitals, dozens of drug companies, and government agencies. But once drugs are entrenched in the market, companies rarely agree to rename them, and the FDA can’t force a change.

When the agency asked Pfizer to add a K to Norvasc, a high blood pressure medication mixed up at least 30 times with Navane, another Pfizer drug used to treat schizophrenia, Pfizer declined. The company says the FDA wanted the K to force doctors to end the word with a tall letter so it would look different. But Pfizer says it didn’t need to add the K because it had run ad campaigns in pharmaceutical journals showing handwritten prescriptions for Navane and Norvasc that looked almost exactly alike. Entitled “To Solve the ‘Prescribble’ Riddle,” the ad warned that brand-name similarities and bad penmanship can turn “a straightforward prescription” into a “mysterious prescribble.”

Joseph Feczko, a Pfizer senior vice president, says the mix-ups virtually stopped after the ad campaigns, and when the company pointed that out to the FDA, the agency stopped pressing. But Mr. Cohen says that since 1995, the year the FDA asked for the name change, his group has received at least 13 reports of the drugs being mixed up.

Pharmacists contribute to mix-ups by failing to counsel patients about their drugs as required by law, pharmacy professors say. Mix-ups can often be averted with “a 10-second intervention” telling the patient what the drug is supposed to treat, says Glen Farr, a pharmacy professor at the University of Tennessee.

Only a few letters have to be the same for drug orders to look alike when a doctor’s handwriting is bad. A novel Texas lawsuit blames a doctor’s handwriting in the death of a patient who received Plendil, an antihypertensive, instead of Isordil, a drug that treats angina. The man had a heart attack within 14 hours of taking the wrong drug, and he died a few weeks later of complications, says Kent Buckingham, a Kermit, Texas, attorney who is representing the deceased patient’s estate. The trial is scheduled to begin later this fall.

Max Wright, the attorney for the doctor, Ramachandra Kolluru, denies the doctor’s handwriting was illegible and says the patient was so ill that the medication mistake had nothing to do with his death.

To get around bad penmanship, groups like the Institute for Safe Medication Practices recommend computerized prescriptions or use of a new prescription pad with icons depicting various body parts. The doctor then circles the part the drug is designed to affect.

Some drug companies have hired companies like Med-Errs, owned by the Institute of Safe Medication Practices, to test some of their names. Med-Errs runs potential drug names through a computer program developed by the University of Illinois, which methodically evaluates how different a proposed trademark is from the 100,000 or so drug names already on the market.
Med-Errs also sends proposed names – written in doctors’ handwriting – to 20 or 30 pharmacists around the world to see if the names cause confusion. One such case was the name Vicard, a proposed name for an injectable diuretic for cardiac-arrest patients. When it was tested, it turned out it sounded too much like bicarb, the slang for sodium bicarbondate. Bicarb is used to reverse acid buildup after cardiac arrest.

Two’s a Crowd Some drug pairs that have been mixed up:
Drug Indication

EVISTA – Osteoporosis
E-VISTA* – Combats itching
Premarin – Estrogen replacement
Primaxin – Antibiotic
Imferon – Iron replacement
Interferon – Cancer therapy
Nicoderm – Nicotine patch
Nitroderm – Nitroglycerin patch for angina
Paxil – Antidepressant
Taxol – Breast, ovarian cancer therapy
Xanax – Anxiety treatment
Zantac Gastric ulcer treatment *Not marketed in U.S. since 1989 but still in reference texts and available in generic form Source: U.S. Pharmacopeial Convention Inc.