Adcock said it remains in talks with Santiago-based CFR, which last month made a cash and share offer to acquire all of Adcock for R73.51 a share, valuing it at R12.9bn.
"The independent board has received further unsolicited proposals," Adcock said in a statement.
It added the board had not received any proposal it regards as "being more favourable" than the CFR offer.
CFR has yet to give specifics on its non-binding offer.
Shares in Adcock fell 1% to R67.45. CFR's offer price is about 9% above the current share price.
Government pension fund and Adcock's biggest shareholder, the Public Investment Corporation, said late last month it would prefer a local buyer for the company.