The document describes bilayer and tri-layer tablets, which consist of multiple layers providing varying drug release mechanisms. Bilayer tablets feature one fast-release layer and one sustained-release layer, while tri-layer tablets have three layers, allowing for combinations of immediate and delayed release. The formulations involve specific steps for dosing and compressing layers to create tablets that provide both quick relief and prolonged action.

1. 1. Bilayer Tablets: These tablet is consist of two layers, typically
with one layer containing a fast-release formulation (for
immediate drug release) and the other containing a sustained-
release formulation (for controlled or delayed release)
2. Example: A painkiller where one layer provides quick relief
while the other ensures prolonged action.
3. 2. Tri-layer Tablet : These tablets have three layers, each
offering different release mechanisms or combinations of
ingredients.
Example: The middle layer can be used for controlled release,
while the top and bottom layers offer immediate or delayed
release.
tyPes of multilayerd Tablet

2. Steps in formulations of
multilayerd Tablet
Dosing of
granules for
bottom layer into
die from first
hopper
Final
Compression of
two layer
tablets into
clear distinct
layers
Precompressio
n of first layer
by first roller
Ejection of
bilayer tablets
Transfer filled
die to
secondroller
for
compression
Transfer of
the prepared
core to
second
hopper
Dosing of the
top layer from
secondhopper
into die
Reduced first
layer to smaller
size in order to
create the
space required
for the second
feeder

3. Machine of multilayerd Tablet

4. Multilayer Tablet and Controlled Release:
Multiple release profile: Provides both immediate and
sustained drug release in one tablet.
 Immediate release layer: Designed with a disintegrating
monolithic matrix for fast drug release to achieve a
peak effect.
 Sustained release layer: Designed with an erodible
monolithic matrix to release the drug slowly,
maintaining plasma drug concentration over time.