(NewsNation) – A drug manufacturer is voluntarily recalling a batch of the blood pressure medication betaxolol over a foreign tablet was found during production.

KVK-Tech called the recall a precautionary measure after a 5 mg oxycodone HCl pill was discovered on the packaging line once the batch was complete, according to a KVK-Tech recall notice published by the U.S. Food and Drug Administration.

The two pills are similar in appearance, and the difference is “not likely to be noticed by a regular user of the 10 mg betaxolol tablet,” according to the notice.

Betaxolol can potentially slow elderly patients’ heart rates — an effect that would likely be exacerbated if it were accidentally combined with an opioid, according to the FDA. It could also worsen some patients’ lung and heart function.

Those taking betaxolol are being instructed to check their medication for batch numbers and expiration dates; the affected lot had a batch number of #17853A and a June 2027 expiration date. The tablets were distributed nationwide to wholesalers and retailers.

Users that may have received betaxolol tablets from the recalled lot are being urged not to take the medication. Anyone who may be experiencing unexpected reactions should contact a physician.

The drugmaker notified its distributors and customers with a recall letter on Sept. 26. KVK-Tech is arranging for all the recalled pills to be returned. The FDA’s website has further information about reimbursement for affected customers.