As Facebook gradually opened pharmaceutical industry pages to public commenting this week, some companies said they had not yet seen troublesome comments, while others continued to move offline to avoid potential risks.

Facebook reversed a policy that exempted all drug company pages from open “walls.” Pages focused on companies themselves and on disease or patient-specific communities are now open to comments, while those focused on a specific prescription product continue to be closed.

Companies have worried that open walls may lead to the reporting of bad side effects, promotion of off-label use or inappropriate statements — all of which could raise concern from government regulators. Like other Facebook users, companies can delete comments once they’ve been posted.

Sanofi, which maintains pages related to diabetes and pertussis (whooping cough), as well as a company page, has seen no problems from the more than 66,000 people who “like” its pages, according to spokesman Jack Cox. Pfizer also has not had any issues, said spokesman Andrew Widger, and monitoring is “running smoothly” for its hemophilia and multiple sclerosis pages, which have more than 3,900 “likes” combined.

Other companies have decided to remove pages over the past couple of days.

Amgen, which had previously planned to maintain its “Breakaway From Cancer” page, removed it Monday. The company sells the cancer drugs Neulasta, Neupogen and Vectibix.

“We’re still working through the issues of comment moderation,” spokeswoman Christine Regan said. Amgen has been working with Facebook, but “we aren’t comfortable with the solutions we currently have,” she added.

Bayer closed its “Strong at Heart” page, which had more than 26,000 likes. The company is instead maintaining its similarly themed “I Am ProHeart” page, which has more than 49,000 likes. Aspirin, the company’s flagship product, has been shown to benefit heart health.

“We have monitoring and response procedures already in place for the ‘I Am ProHeart’ page,” so consolidating the two pages makes that work more easily, spokeswoman Anne Coiley said.

Purdue Pharma closed its “In the Face of Pain” page, which had more than 250 likes. The company sells the pain medications Butrans, Dilaudid, MS Contin and Ryzolt. Spokeswoman Libby Holman said Purdue might reevaluate its decision when the Food and Drug Administration releases guidelines for online engagement.

Johnson & Johnson removed four of its pages Monday, as it had said last week that it would. AstraZeneca removed one page Friday.