Tablet hardness is  not a part of pharmacopoeia specification but you have to decided the lower and higher limit to produce a quality product. If  there is no impact of hardness on Drug Product specification ( release and stability) and in- vivo study,You have to set the lower limit for tablet which must withstand the attrition during the process and transportation.

the pressure  play  a importendt rol in the  drug disintegastion (PO) the water can not be difuss easy ibetween drug kristal and the explovie material (corn strech) to disolution the drug molekül and make it competent  to  difusion in the blood.

diffrent pressure in the produktion is diffrent PK of the same Drug like.

this is the magical point of Bioäquivalenz.

Hardness can impact disintegration, dissolution and bioavailability, so it's  a good routine QC test to run. And USP  is quick and easy. You might also like to test for friability (USP ) to ensure they aren't so hard they are flaking and cracking. Does your tablet ever need to be broken in half? Check USP for rules on functional scoring. 

 Testing tablet hardness is  ensuring the mechanical integrity of produced tablets during subsequent processes. Hardness of a tablet directly relates to pharmacokinetics as disintegration time , dissolution time, absorption process, distribution and elimination. There is no such official specification is given in any pharmacopoeia about the hardness of the material and hardness test. Formulator should have to decide and maintain the range of hardness during preparation based upon requirement and type of the formulation.

Dear All,

Thanks a lot for your answers. My concern was that, during development phase, for some of the products the hardness is very low about 18 to 20N. However, these tablets passes the friability test. So, is it ok to proceed further or do we need to focus on increasing the hardness?

Regards,

Abhishek

Dear Abhishek;

If your tablets pass the friability test and during packaging it creates no problem; then you can go ahead.

The acceptable range is 8-13 kp (cant remember conversion to N). Also, usually the way to make suitable tablets for immediate release is solid fraction > 0.85. If its chewables, 0.7 is sufficient. Do you know the solid fraction of your tablets?

Please clear me if there are 3 tablet having different hardness with increasing order which one of the in body dissolved in body after taking it. How it can be valuable for any one. Please provide me at reference in this regards.

Although there is not definite number for the hardness of the tablet, there is a recommended range which is most likely sufficient for handling, this is between 1.5-4 MPa or approx 15-40 Newton. The reason the hardness of a tablet is not definite is due to the broad aspect of the word "tablet". Some tablets like ODT's have fast disintegration expectation and as such are required not to be very strong or to have super disintegrating properties while others are expected to a much slower release mechanism ( very much dependent on porosity). Tablet shape can also play a role in strength/friablity as flat cylindrical tablets tend to have higher friability than their convex counterparts. Technically, a weak compact used of inhallation (For inhallers) is also a tablet.