# Bioequivalence and Bioavailability Forum

Back to the forum  Query: 2017-06-27 02:04 CEST (UTC+2h)

## Calculation of Loading and Maintenance dose for Sustained release tablet [PK / PD]

Dear sir,

I am working on a project for development of Sustained release tablet (once or twice daily) against immediate release tablets (Conventional: 3 times a day, tau 8 h).
I have calculate Loading dose (Css X Vd), Rate for maintenance dose (Css X CL), Dose to be maintain (Total daily dose of Immediate release tablets - Loading dose), No. of hours required for maintenance dose (Maintenance dose / Rate for maintenance) and Total no. of hours for complete drug release (Tmax + No. of hours required for maintenance dose).

My questions are-
1. For the above calculation, I have consider the values of AUC last, Vd, CL, Tmax from the literature of drug of multiple oral doses. Am I right?
2. Is the obtained loading dose concentration (mg/h) for first hour or Tmax or anything else?
4. Is that I am right or wrong for calculating Total no. of hours for complete drug release as mentioned above ?
5. By the above mentioned formula of Total no. of hours for complete drug release, the obtained answer is less than 24 hours. Then how should I claim that my SR tablet is sustainable for 24 hours ?
6. How can I calculate the no. of hours for maintenance dose till 24 hours considering the Rate for maintenance dose? and their release concentration required for every one/two hours till 100 % release at 24 hours ?
7. Can I plan for two sustained release tablets against three Immediate release tablets having same daily dose ?

Your reply will be benchmark to me for thinking here onward on such projects.

Regards,
Dr. Amolkumar

• Calculation of Loading and Maintenance dose for Sustained release tablet - Dr. Amolkumar, 2017-04-13 13:27 [PK / PD]
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