Question

Explain why we change the dose of the drugs in specific patients with example (Don't copy from your slides or internet).

Answer 1

Drug Dose–Response Relationships

Drug dose–response relationships are important in assessing the efficacy and potency of drugs. They are also useful for the interpretation of drug and receptor interactions. There are two types of drug dose–response relationships, namely, the graded dose–response and the quantal dose–response relationships. In the graded dose–response relationship, the tissue will respond to the administered drug until it reaches maximal response as the drug concentration is increased. The occupancy of the receptors by the drugs also plays a critical role in determining the response and is stated to be proportional. A drug’s potency can be derived from a graded dose–response curve . The EC50 is the concentration which brings about 50% of the maximal tissue response and is used to determine the potency of drugs .

(NOTE: Drug doses should be increased for any breakthrough seizure that is unprovoked or due to provoking factors that are difficult to avoid and likely to recur (e.g., febrile illness, missing or delaying a single medication dose due to vomiting or forgetting). )

Adjusting the dosage regimen frequently is required as one administers drugs to diseased animals, because the dosage regimens have been worked out in healthy, normal animals. Adjustment is indicated when drug elimination or the volume of drug distribution alters significantly in the animal. In general the following are true:

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If the volume of distribution changes, one must change the drug dose.

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If the elimination half-life of the drug changes, one must change the dosing interval.

For drug dosage regimens determined by TDM, one makes modifications based on a percentage:

New Dose=Old Dose×(Target Concentration÷Measured Concentration)

And i discus about the reason

1. Tolerance of one drug take a patient once a day this drug potency depend

2. Depended 2nd main reason

3. A patient take a drug in one dose per day but he will tolerate this dose concentration but the effect of the drug is not same dose because his mind set up and his ability is increased than old dose so we change the dose of the drug and gave the effect .

Example : insulin we take per day but the potency of the drug tolerable by the patient in this cause we increase the dose of the drug .

And another example is physicotic drug eg . Benzodiazepine.

Thank you .