Clinical Significance of pKa in Pharmacology

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What are the main routes of drug administration mentioned in the text?

Oral, subcutaneous, nasal, topical

Buccal, intrathecal, intraventricular, intra-articular

Intramuscular, intravenous, intradermal, transdermal

Oral, sublingual, rectal, inhalation (correct)

Which of the following factors influences drug absorption related to the absorbing surface?

Body weight

Local blood flow (correct)

Eye color

Hair length

In which pH environment are acidic drugs more ionized?

Basic

Neutral

Acidic

Alkaline (correct)

Which route of administration is generally the fastest for drug absorption?

Intravenous Signup and view all the answers

What type of drugs are more absorbed: ionized or nonionized?

Nonionized (non polar, non charged) drugs Signup and view all the answers

How does ischemia affect drug absorption?

Decreases absorption Signup and view all the answers

What is the formula for calculating the volume of distribution (Vd) of a drug?

Vd = Total amount of the drug in the body / Plasma concentration of the drug Signup and view all the answers

What does a total Vd of less than 5 L indicate about the drug's distribution in the body?

The drug is present only in the vascular compartment and can be removed by dialysis. Signup and view all the answers

How can toxicity with acidic drugs be treated effectively?

By alkalinization of urine, which renders the drug more ionized in urine and less reabsorbable. Signup and view all the answers

In what pH environment are basic drugs more likely to be trapped in breast milk?

Basic drugs with pKa >7.2 are more likely to be ionized and trapped in breast milk due to its pH of 7. Signup and view all the answers

What does a total Vd greater than 41 L indicate about a drug's distribution in the body?

The drug is highly bound to tissue proteins and cannot be removed by dialysis. Signup and view all the answers

How can toxicity with basic drugs be effectively managed?

By acidification of urine, which renders the drug more ionized in urine and less reabsorbable. Signup and view all the answers

What is the purpose of phase I metabolism in drug metabolism?

Introducing a polar group to render the molecule polar and water soluble for excretion. Signup and view all the answers

Which enzymes are responsible for catalyzing phase I metabolism?

Cytochrome p450, esterases, deaminases. Signup and view all the answers

What is the role of glucuronyl transferase in phase II metabolism?

It catalyzes conjugation reactions with glucuronic acid to form water soluble conjugates. Signup and view all the answers

Define 'First-Pass' Metabolism in the context of drug administration.

Metabolism of drug at the site of administration before it reaches systemic circulation. Signup and view all the answers

What is the bioavailability of a drug administered via the intravenous (IV) route?

100% Signup and view all the answers

How does the bioavailability of atenolol compare to lidocaine, propranolol, and morphine?

Atenolol has complete bioavailability, while lidocaine has partial bioavailability. Propranolol and morphine are in between. Signup and view all the answers

What is the formula to calculate the loading dose needed to attain a desired plasma concentration?

LD = Vd x Cp Signup and view all the answers

Why is it essential to consider drug clearance in pharmacokinetics?

Clearance (Cl) helps determine the rate at which a drug is removed from the body, influencing dosing frequency and overall drug effectiveness. Signup and view all the answers

How does binding of drugs to plasma proteins impact drug efficacy?

The effect of a drug is related only to its free part, as the bound part acts as a reservoir that prolongs the drug's effect. Signup and view all the answers

Which organ is the major site of drug metabolism in the body?

Liver Signup and view all the answers

Give an example of a drug that undergoes metabolism to produce an active metabolite.

Codeine to morphine Signup and view all the answers

How can diseases affecting albumin levels impact drug therapy?

Diseases like chronic liver disease, pregnancy, and renal failure can alter albumin levels, affecting drug binding and potentially leading to drug-related issues. Signup and view all the answers