Zantac contamination worries pharmacies

The U.S. Food and Drug Administration warned millions of people who use a popular heartburn medicine that it contains a possible carcinogen, but officials have not told anyone to stop using it yet. Several pharmacies and producers have stopped selling the drug ranitidine, known by the brand name Zantac, over the past several weeks.

Walmart pulled the medication from its shelves on Wednesday, following CVS on Monday and Walgreens and Rite Aid earlier.

“We began testing ranitidine products immediately after we learned of the potential impurity,” Acting FDA Commissioner Ned Sharpless said. “We will continue to investigate and work to ensure these types of impurities do not exceed acceptable limits so that patients can continue taking the medicines they need without concern.”

In September, the FDA said it found low levels of a chemical called NDMA, which is thought to cause cancer, in drugs that use ranitidine to treat ulcers and acid reflux. NDMA is also found in water and foods, including meat, dairy products, and vegetables. The agency initially said the drugs contained comparable levels of the chemical to what is usually found in the environment. But the FDA released an update on Wednesday saying, “Early, limited testing has found unacceptable levels of NDMA” in samples of ranitidine.

The online pharmacy Valisure also reported higher levels of NDMA and suggested the instability of the ranitidine molecule caused the problem rather than production processes cited by the FDA and others.

WebMD estimates that doctors write more than 15 million prescriptions for ranitidine each year, and that doesn’t count the number of people who buy it over the counter.

Other countries, including Italy and Canada, have issued limited recalls or blocked the drugs from the market because of the contamination.

Zantac maker Sanofi said Monday it is working with the FDA and carrying out its own investigation, but it hasn’t stopped selling the product. Last week, two companies that make generic versions of the drug put out a recall on their ranitidine products, though both Apotex and Sandoz said they had received no reports of consumers getting sick.

NDMA has already caused recalls of dozens of prescription blood pressure and heart failure drugs in the last year. The FDA found higher levels of the chemical in those drugs. Initially, it estimated that among people who took the highest dose of the contaminated drugs for four years, there would be one additional case of cancer for every 8,000 people. But the agency clarified that was a worst-case scenario and most patients had been exposed to much smaller doses.

A giant leap

SpaceX unveiled a prototype of a rocket last week that could one day carry people to the moon or Mars and back to Earth. Elon Musk, CEO of the private spaceflight company, introduced the public to the shiny, massive Starship rocket on Saturday at a launch facility near Brownsville, Texas.

“I think we should do our very best to become a multiplanet species, and we should do it now,” he said.

Musk, who is also the entrepreneur behind the electric car company Tesla, has cast grand visions before. In 2017, he said SpaceX would take two tourists to the moon and back within a year. The trip keeps getting postponed and now has an estimated launch date of 2023.

So far, SpaceX has not sent a single human into space, but it has accomplished something no other space agency has: The first-stage booster of the SpaceX Falcon 9 rocket can make a controlled descent over land, touching down without crashing. Astronauts previously jettisoned booster rockets into the ocean. Some were fished out for reuse while others were abandoned to the seafloor.

To carry people to the moon, Musk’s Starship will need a boost from a new megarocket that SpaceX is developing called the Super Heavy. In another month or two, SpaceX plans to test the Starship on its own, shooting it to an altitude of 12 miles and then bringing it in for a landing. —Lynde Langdon

Sucked in

NASA announced last week a planet-hunting satellite had witnessed a cosmic cataclysm from the start for the first time. The Transiting Exoplanet Survey Satellite (TESS) watched a black hole tear apart a star. Scientists first observed the event, called a tidal disruption, on Jan. 29 and published a paper about it last week in The Astrophysical Journal. Astronomers have only ever observed 40 tidal disruptions, and this was the first one they spotted as soon as it began.

“The early TESS data allow us to see light very close to the black hole, much closer than we’ve been able to see before,” said Patrick Vallely, a co-author of the study. —L.L.

Fighting the flu

Scientists worry the flu vaccine developed for this year might not work well. The vaccine’s makers base it on the dominant strains of the virus from the previous year. The flu season wrapping up now in the Southern Hemisphere, a harbinger of what the Northern Hemisphere will face, has a few dominant strains that our vaccine doesn’t cover. Doctors still advise getting the shot because it makes the illness less severe in people who still catch the flu after getting vaccinated. —L.L.