Pharmacology question HELP

For doxycycline, more than 90% of the drug is bound to plasma proteins. It is also known that this drug is almost completely absorbed from the GI tract.
I thought that drugs bound to plasma proteins cannot be absorbed to be distributed to the tissues. If more than 90% are bound to plasma proteins, how can doxycycline be almost completely absorbed from GI tract?

Thanks in advance!

Source: Student Doctor Network - February 18, 2018 Category: Universities & Medical Training Authors: aspiringmdgirl Source Type: forums