Drugs That Oughtn’t Mix Often Prescribed, Study Finds

Some pharmacies, and some doctors, are lax about prescribing and dispensing drugs that should not be taken at the same time, a new study has found.

Researchers for the Degge Group in Arlington, Va., which studies the pharmaceutical industry, retrospectively analyzed prescribing patterns for cisapride, a heartburn medication that was withdrawn from the market last year after it was blamed for causing irregular heartbeats in 270 patients, 70 of whom died. Most of those cases involved use of cisapride with contraindicated drugs--drugs that package inserts and other information specifically warned against using at the same time as cisapride.

The researchers reported in the Oct. 3 Journal of the American Medical Assn. that 3% of 131,000 cisapride prescriptions they studied were dispensed with at least one contraindicated drug.

Of those inappropriate combinations, 50% were prescribed for patients by the same physicians and 89% were dispensed by the same pharmacies.

The group was not able to examine how often computerized monitoring systems, employed by many pharmacies, blocked such inappropriate combinations. They argued that the systems should be more widely adopted and improved to reduce the incidence of such prescriptions.

Gene Identified for Some Forms of Lou Gehrig’s

Two groups of researchers have identified a second gene that causes an inherited form of Lou Gehrig’s disease, a finding that should help explain the workings of the more common sporadic form.

Between 5% and 10% of the 30,000 U.S. cases of the disorder, properly called amyotrophic lateral sclerosis, or ALS, are the inherited form.

Researchers had previously identified a gene that causes about 20% of the inherited cases, but the cause of the rest of the inherited cases--as well as all others--remained a mystery.

The researchers studied families in Saudi Arabia, Tunisia and Kuwait that had a high incidence of an unusual form of ALS that manifests itself before age 25 and progresses more slowly than sporadic ALS.

They reported in the October Nature Genetics that this disease is caused by a mutated form of the gene that serves as the blueprint for a protein called alsin. Although they do not yet know how the defective gene causes the disease, they believe that lack of alsin’s normal function is at the root of the problem.

High Lead Levels Found in Iron-Deficient Children

Children who have an iron deficiency are more likely to have high levels of lead in their blood, especially if they live in high-lead environments, say researchers from UC Berkeley.

Although scientists are not sure why the correlation exists, they speculate that a body that is iron-deficient might be more likely to grab on to lead and other heavy metals to take its place--even though those metals can be toxic.

Epidemiologist Asa Bradman and his colleagues studied children, age 1 to 5, in 319 Sacramento homes, measuring levels of lead and the iron-containing chemical ferritin in their blood. Bradman’s group reported in the Oct. 3 Environmental Health Perspectives that the iron-deficient children had significantly higher levels of lead in their blood. In low-lead-level homes, the iron-deficient children had lead levels of 5.6 micrograms per deciliter, compared with 4.6 mcg/dL in the children with normal lead levels. The difference was 2.8 mcg/dL in high-lead-level homes. The report is available at https://ehpnet1.niehs.nih.gov/docs/2001/109p1079-1084bradman/abstract.html.

Latinos Using Drug Banned in the U.S.

A potentially dangerous fever and pain drug that is banned in the United States but available in Mexico is widely used by Latinos in Southern California, according to UC San Diego researchers.

Few physicians are aware of problems with the drug, they found. The drug is dipyrone, which is sold in Mexico as Neo-melubrina. It is banned in this country because it sometimes produces agranulocytosis, a dangerous depletion in white blood cells that can lead to potentially fatal infections.

Dr. Lori Taylor and her colleagues surveyed 200 Latino parents and found that 38% had used dipyrone for themselves or a family member, the team reported in the September Western Journal of Medicine. And among 535 health-care providers questioned, 70% were unfamiliar with the drug’s adverse effects.

Repeated Steroid Doses Could Harm Fetuses

Repeated administration of steroids to pregnant women who are at risk of premature birth does not appear to be beneficial and may actually be harmful.

A single dose of steroids given two to seven days before premature birth can reduce the risk of lung ailments and death in the infants. But if the child is not born within that time period, physicians often repeat the steroid shots weekly. It is that practice that is dangerous and should be abandoned, according to researchers from the University of Colorado and the Denver Medical Center.

Dr. Debra Guinn and her colleagues studied 502 women at risk of pre-term birth. The women were given a single course of steroids at the beginning of the study, then either a placebo or the steroid beclamethasone every week for an average of four weeks.

The team reported in the Oct. 3 Journal of the American Medical Assn. that complication rates were about the same in babies in both groups. A difference was observed only in babies born before 28 weeks; severe respiratory distress syndrome developed in 66% of those whose mothers received weekly steroids versus 89% in the placebo group. But their results also showed that babies whose mothers had the weekly shots were more likely to develop bleeding in the brain, and researchers stopped the study early as a result.

Promising New Drug to Treat Fatal Ailment

An experimental drug can ease the symptoms of primary pulmonary hypertension, making it potentially the first effective oral drug for treating the disabling disorder.

Primary pulmonary hypertension is a progressive narrowing of the small blood vessels in the lungs, which leads to enlargement and failure of the right ventricle of the heart. Its cause is not clear. The disorder, which is usually fatal, leaves patients breathless and unable to do many everyday tasks.

Current treatment involves continuous intravenous administration of a drug, but average survival is only three years. A new drug, bosentan, acts by blocking the action of a protein called endothelin, which is thought to be the cause of the disorder.

Dr. Richard Channick and his colleagues at UC San Diego studied 32 patients with the disease who were randomly assigned to receive either bosentan or a placebo. They reported in the Oct. 6 Lancet that, by the end of 12 weeks, patients receiving the drug were able to walk an additional 70 yards in a standard six-minute walk, while those taking a placebo walked 6 yards less. Blood pressures in the lungs of those receiving the drug also fell, while it rose in those taking the placebo.

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Medical writer Thomas H. Maugh II can be reached at [email protected].