Glidants are excipients that are used in Oral Solid dosage forms to enhance the flow of powders or granules.

Definition Of Glidant

Glidants are the excipients that increase the flow of powders or granules by reducing interparticle friction.



Other Name Of Glidants

Glidants are also known as Flow Promoters.

Mechanism Of Working Of Glidants

The working mechanism of glidants is simple & they promote flow by following mechanisms,

  • Reducing Friction
  • Reducing Surface Charge

How Do Glidants Reduce Friction?

Powder or granules flow is reduced due to their irregular shapes. Glidant particles arrange themselves between irregularities & give a spherical shape to the particles or granules.

Due to the spherical shape, friction between particles is reduced & flow is increased.

Functions Of Glidants

Glidants used in formulation provide the following functions.

  • Improve Flow
  • Reduce Friction
  • Reduce Charge
  • Help To Prevent Weight Variation

Effect Of Glidants On Product Quality

Product quality is always dependent on smooth & trouble-free manufacturing operations. If there is any problem during the manufacturing process it will seriously affect the product quality.


Let’s take the example of the tablet compression process in which we add powder or granules in the hopper of the compression machine & from the hopper these powders or granules move towards the feeder for die filling.

If there is a flow problem of powders or granules, it may result in the following defects,

  • Weight Variation
  • Low Hardness 

Read Details

Weight Variation During Tablet Compression

Why Do We Use Glidants?

We use glidants to improve the flow of powders or granules during the following process,

  • During Tablet Compression
  • During Capsule Filling
  • During Dry Powder Suspension Filling
  • Dry Powder Sachet Filling

As we discussed in the above example due to flow issues during compression weight varying and low hardness tablets are compressed in the same way during capsule filling, dry suspension filling & sachet filling process, weight variation in filling weight occurs, so to overcome this issue we use glidants in our formulations.

When We Use Glidants?

Glidants are added in our formulation at the final blending step of wet granulation, dry granulation, or direct compression process.

We add glidants after sieving because sieving increases the surface area.

Mixing Order Of Glidants

In the final blending step, first we add other excipients & mix them with powders or granules depending on the formulation.

Two excipients are used at the end, one is glidants and the others are lubricants.

Glidants are added just before the lubricants or in simple words, glidants are added at the 2nd last number.

Disadvantages Of Glidants?

It is a very important point to remember that the glidants effect is concentration dependent so always use optimum & recommended concentrations of glidants.

If we use glidants in excess quantity it will create a negative effect & will hinder or retard the flow.

Examples Of Glidants 

Examples Of commonly used glidants are given Below,

  • Talc
  • Colloidal Silicon Dioxide
  • Syloid
  • Corn Starch

Importance Of Glidants

Glidants are very important for our formulation because of the following main reasons,

Product Quality

Due to improved flow, product defects are prevented & good-quality product is manufactured 

Process Cost

If product flow is not good our process will not be smooth so it will take extra time for troubleshooting & overall process cost will be increased due to downtimes.

Read More

  1. Lubricants Used In Pharmaceutical Industries
  2. Colloidal Silicon Dioxide
  3. Classification of Excipients.
  4. Role of diluents in tablet granulation.
  5. Role of mannitol in pharmaceutical products.
  6. Uses of Starch and modified starch in tablet manufacturing.
  7. Different Grades of Microcrystalline Cellulose or Avicel .
  8. Role of Lactose in tablet manufacturing.