Podcast Beta
Questions and Answers
What percentage of penicillin G administered intravenously will be eliminated in the urine at one hour?
How much of the initial concentration of ascorbic acid remains after two half-lives in an aqueous solution?
What is the maximum allowable degradation of cocaine to maintain its shelf-life at 40 °C and pH 7.25?
What percentage of ranitidine would be eliminated from the body after 4 hours considering its elimination half-life of 2 hours?
Signup and view all the answers
If dopamine is administered at a dose of 5 μg/kg/min for a 70 kg patient, what is the total infused volume needed per minute?
Signup and view all the answers
What is the shelf-life of ascorbic acid at shelf temperature if it becomes unacceptable when its initial concentration is reduced by 1/8?
Signup and view all the answers
How long will it take for all of the administered dose of penicillin G to be eliminated?
Signup and view all the answers
After an intravenous bolus dose of a drug with a half-life of 0.5 hours, what is the remaining concentration after 3 hours?
Signup and view all the answers
How many moles of sodium chloride are present in 10g?
Signup and view all the answers
To prepare 100ml of 1M NaCl, how many grams of NaCl are needed?
Signup and view all the answers
How many milliequivalents of Na ion are in 92mg/ml of NaCl salt?
Signup and view all the answers
What is the concentration in mg/ml of a solution containing 2mEq of KCl per ml?
Signup and view all the answers
What is the concentration of a solution in mEq/L that contains 10mg% of Ca+2?
Signup and view all the answers
According to the Henderson-Hasselbalch equation, what is the pH when the pKa is 9 and the ratio of non-ionized to ionized species is 10:1?
Signup and view all the answers
What is the pH of a solution containing 0.01 moles of acetic acid and 0.1 mole of sodium acetate per liter?
Signup and view all the answers
What is the dose of paracetamol for a 25kg child if the adult dose is 3000mg daily?
Signup and view all the answers
What is the acceptable shelf-life of ascorbic acid in aqueous solution if it is unacceptable when its initial concentration is reduced by 1/8, given the half-life is 8 months?
Signup and view all the answers
Under conditions of 40 °C and pH 7.25, what is the maximum shelf-life for cocaine if no more than 10% degradation is allowed?
Signup and view all the answers
What percentage of ranitidine would be eliminated from the body after 4 hours given its elimination half-life is approximately 2 hours?
Signup and view all the answers
What rate (mL/min) should the dopamine solution be infused to achieve a dose of 5 μg/kg/min for a 70 kg patient?
Signup and view all the answers
How much volume of a solution containing 3 mg in 10 mL is needed to prepare 15 mL of a formulation requiring 0.002 g of phenylmercuric nitrate?
Signup and view all the answers
What is the concentration representation of a solution described as 0.05 percent?
Signup and view all the answers
How much of a 10% injection is required to create 100 mL of a mixture containing 7.5 mg in 2.5 mL?
Signup and view all the answers
Using first order kinetics, if essential degradation is measured, what would be the degradation extent of cocaine in terms of percentage after 10% limit?
Signup and view all the answers
What is the number of moles in 10 grams of a substance with a molecular weight of 58.5 g/mol?
Signup and view all the answers
What is the equivalent weight of sodium (Na) with a molecular weight of 23 and valence of 1?
Signup and view all the answers
If the concentration of calcium in a solution is 10 mg/100 ml, what is its equivalent in mg/L?
Signup and view all the answers
What is the milliequivalent (mEq) of 1.5 grams of a weak base with an equivalent weight of 74.5 mg?
Signup and view all the answers
For a weak acid with a pKa of 4.15 and a concentration of 0.1 M, what is the pH?
Signup and view all the answers
What is the calculated pH for a weak base if pKw is 14 and pKb is 4.56, with a base concentration of 0.5 M and salt concentration of 0.05 M?
Signup and view all the answers
What is the relationship of concentrations represented by x/y if the logarithmic equivalent is given as 1 in the weak acid formula?
Signup and view all the answers
What is the equivalent weight of KCl with a valence of 1 and a molecular weight of 74.5 g/mol?
Signup and view all the answers
What is the amount of drug entering the liver (CA) when 80mg of the drug is administered?
Signup and view all the answers
What is the formula used to calculate hepatic clearance?
Signup and view all the answers
In the context of pharmacokinetics, what does ER stand for?
Signup and view all the answers
If the elimination half-life (t1/2) is 2 hours, how much of a 100mg drug remains after 4 hours?
Signup and view all the answers
How is the dose of dopamine calculated for a patient weighing 70kg if the dosage rate is 5 micrograms/kg/min?
Signup and view all the answers
If the bioavailability (f) of a drug is 40% and the extraction ratio (ER) is 0.6, what is the calculated F?
Signup and view all the answers
How long approximately will it take for a drug with a clearance (k) of 0.08 to reach 90% elimination (t90)?
Signup and view all the answers
What will be the volume of solution required to obtain a 0.35mg dose of dopamine from a 200mg in 500ml solution?
Signup and view all the answers
Study Notes
Pharmacokinetics and Drug Elimination
- Penicillin G has an elimination half-life of approximately 0.5 hours.
- Administered IV every six hours, half the dose will be eliminated within one hour, leading to minimal accumulation (option B).
- Cocaine degrades at a half-life of 5 hours; degradation should not exceed 10%, resulting in a shelf-life of approximately 0.76 hours (option A).
- Ranitidine's half-life is about 2 hours, with 75% eliminated 4 hours after administration (option D).
- The pharmacokinetic parameters for any drug indicate its elimination behavior and necessary administration intervals.
Ascorbic Acid Shelf-Life
- Ascorbic acid decomposes by first-order kinetics with a half-life of 8 months.
- Reduction of initial concentration by 1/8 is deemed unacceptable, leading to an acceptable shelf-life of approximately 1.5 months (option C).
Drug Dosage Calculations
- For dopamine infusion at 5 μg/kg/min for a 70 kg patient, a volume infusion rate of 0.88 mL/min is calculated (option C).
- For preparation of sulfacetamide eye drops, 5.0 mL of phenylmercuric nitrate solution is required to formulate 15 mL of the complete preparation (option D).
- A 10% injection of a drug to make 100 mL having 7.5 mg in 2.5 mL requires 3 mL of the 10% solution (option C).
Molar and Milliequivalent Calculations
- To prepare a 100 mL 1M NaCl solution, 5.85 g of NaCl is needed (option A).
- There are 4 mEq of Na+ in a 92 mg/mL NaCl solution (option D).
- The equivalent weight of KCl is 74.5, leading to a concentration of 149 mg/mL for 2 mEq of KCl (option B).
pH and Buffer Solutions
- Henderson-Hasselbalch equation can be utilized: for a weak base at pKa 9 with a 10:1 base to salt ratio, pH equals 10 (option C).
- A solution of 0.01 moles of acetic acid and 0.1 mole of sodium acetate yields a pH of 5.15 (option A).
- For a buffer with pH 5 and pKa 4.00, a salt/acid ratio of 10:1 is required (option A).
Pediatric Dosage Calculations
- For a 25 kg child based on a 3000 mg adult dose, the correct dosage is approximately 1200 mg (option A).
- The dosage of paracetamol for a 2-month-old baby from an adult dose of 3000 mg is estimated to be around 40 mg (option A).
Hepatic Clearance
- Hepatic clearance can be computed as CLH = CLT - CLR, with values indicating the importance of understanding drug metabolism by the liver.
Additional Scientific Concepts
- The ratio of ionized to unionized acetic acid affects the pH significantly; a 100:1 ratio with pKa 5.5 results in a pH of 7.5 (option A).
- The calculation of doses and equivalent weights is essential in pharmacology for accurate medication administration and formulation.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Related Documents
Description
Test your knowledge on the pharmacokinetics of Penicillin G in this concise quiz. Understand its elimination half-life and dosage implications for effective treatment. Perfect for students and professionals in the field of pharmacology.
