5.2.3. Ocusert

In this type of system, in between two transparent microporous membranes a drug reservoir layer containing a pilocarpine-alginate complex is fabricated (Figure 14). The porous membrane permits the tears to permeate into the layer containing the drug. When the microporous membrane comes into contact with the tear fluid, it will dissolve and constantly deliver the pilocarpine at a rate of 20 to 40 mcg/h for treating glaucoma disease [136].

**Figure 14.** Ocusert: (1) and (4) show transparent polymer membranes, (2) shows a titanium dioxide white ring, and (3) shows a pilocarpine core reservoir (adapted from [136]).
