Question

a certain drug is effective in treating a disease if the concentration remains above 400mg/l the initial concentration is 850mg/l .it is known that the drugdecays at a rate of 11%of the amount present each hour .

1.to be effective the concentration must be above 400mg/l,but below the safe level of 1000 mg/l.modify your model to include periodic maintenance doses .state the modified dynamical system of equations .

2.experiment with different initial and maintenance dosage amount to prescribe a treatment plan that is both safe and effective and convenient for the patient ,note that hourly doeses are not convenient for a patient think about for example (twice daily,every 4 hours....)give the initial dose and maintenance dose and frequency.

Answer 1

In regular doses, drug concentration acheiving with steady state end result plasma drug concentration reaches a point at dose rate and the clearance rate will be equal after about five half-lives..because of this we can expect drugs will have some sort of long-term effects..A loading dose rapidly achieve the peak level with clearance,so that the desired effect is achieved and maintained sooner...loading dose is calculated by multiplying the desired peak concentration by the volume of distribution of the drug...

Here concentration dose 400mg/dl.concentration dose should be continued for 4 to 5 half lives of the drugs will reach the steady state level..

Maintenance dose mg/l calculated by

MD = CpCL/F

CP = desired peak concentration of drug( mg/ l)

CL = clearance of drug in body( L/h)

F= bioavailability

Dynamical systems are explained by one or more equation,that involve over time...it change with time, usually very complex having many complements with you involved relationship..

Dynamical systems helps me understand the relationship between the rates of absorption, distribution,and elimination process of the drug within the body helps to establish the desired therapeutic response..