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Right choice is (B) Solutions

The best explanation: Solutions are readily available. Thus having the highest BIOAVAILABILITY. Tablets take time to disintegrate. The ORDER of decreasing bioavailability will be, solutions > emulsions > suspensions > capsules > tablets > coated tablets > enteric coated tablets>SUSTAINED released products.

Right choice is (b) False

For explanation: LOW CONCENTRATION water soluble dye have inhibitory EFFECT on the DISSOLUTION Rte OF SEVERAL crystalline DRUGS. The dye molecules get adsorbed on the crystal faces and inhibit drug dissolution.

The correct option is (C) Tagging the drug with a radioisotope and scanning the stomach

For explanation I would say: In VIVO gastric emptying of a drug can be studied by using radio-opaque CONTRAST materials like BARIUM sulphate. It can also be studied by tagging the drug with a radioisotope and scanning the stomach at regular INTERVALS.

Right ANSWER is (b) Acidic Drugs

The BEST I can explain: Due to the acidic pH of the STOMACH, which is due to the secretion of HCL into the stomach, only acidic DRUG absorption is favoured. But this is possible only if the drugs are soluble in the gastric fluids because most of the drugs get UNIONIZED because of the lower pH.

The CORRECT option is (C) Dissolves only in alkaline pH of the intestine

Easy explanation: The enteric COATED TABLET only dissolves in the alkaline environment of the intestine. It may take 2-4hrs for the enteric coated tablet to empty form the stomach to the intestine.

The correct option is (a) True

For EXPLANATION I would say: The statement is true. The thickness of stratum corneum, PRESENCE of hair follicles, trauma, hydration of skins, grooming, exposure to the chemicals DETERMINE the passive absorption of DRUGS from the surface of the skin to below. This list also includes the age of the patient, the environment humidity, and TEMPERATURE, permeation of the enhancers and use of other drugs.

Right option is (a) TABLET disintegration to granules

For explanation: The rate at which drug will be getting absorbed from the drug from the BLOOD depends UPON the drug formulation. In the case of a tablet, the disintegration of the tablet into smaller particles will be the SLOWEST step.

Correct choice is (a) Microvilli

To explain I would say: The surface of the SMALL INTESTINE folds into projections called villi. The surface of each villus has further smaller projections KNOWN as microvilli. About 600 protrudes from each absorptive cell that lines the villi. Thus INCREASES the surface AREA by 600 times.

Correct option is (d) LIPOPHILIC, NEUTRAL, BASIC drugs

Explanation: The PH of the mouth is 6.8. So no ACIDIC drug can get absorbed through the lining of our mouth. Only lipophilic drugs, neutral drugs, and basic drugs get absorbed into the systemic circulation.

The correct choice is (B) Film coating

Easiest explanation: Film coating is thin and dissolves rapidly and thus don’t affect DRUG absorption. Sugar coat is TOUGH and TAKES a longer time than film coating to dissolve.

The correct answer is (d) 450cm

The best I can explain: The mean length of GIT tract is 450 cm. The gastrointestinal tract comprises of a number of COMPONENTS whose primary FUNCTION is secretion, digestion, and absorption.

The correct choice is (c) Fine PARTICLES dissolution

Easy EXPLANATION: The step of drug dissolution is generally rapid due to the large surface area of the particles. FACTORS which are essential in drug dissolution from the suspension are particle SIZE, polymorphism, wettability, ETC.

The CORRECT ANSWER is (a) True

The explanation: Liver is the most important and the major site for DRUG metabolism. It also includes the FIRST PASS metabolism.

Right choice is (a) True

The explanation: Aging of drugs AFFECTS DRUG RELEASE. It happens mostly with shellac coated drugs. Experiments showed that shellac coated tablets STORED for 2 years have a 60% decrease in their plasma level.

Right option is (c) Skin

The BEST I can explain: The LARGEST organ of the BODY is the skin. The weight is approximately 2kg and the surface area is about 2-meter square. It receives about 1/3rd of the total blood CIRCULATION of the body.

The CORRECT choice is (a) True

The best explanation: The passage from the stomach to the small intestine is called gastric emptying. This also is the rate-limiting step in CASE of DRUG absorption because the major site of drug absorption is the small intestine.

Correct answer is (b) False

For explanation I would SAY: The statement is false since the gastric PH of infants is high. The intestinal SURFACE and the blood flow to the GIT is low thus RESULTS in altered absorption pattern in comparison to adults.

The CORRECT CHOICE is (d) Limited surface area

Explanation: The advantage of the sublingual and buccal route is rapid absorption, higher blood level due to the HIGH vascularization of the oral cavity. No first-pass hepatic METABOLISM that is no passing through the liver. No degradation of drugs such that encountered in the GIT. The presence of SALIVA helps in drug dissolution and its permeation.

Right choice is (a) True

The explanation: HYDROPHOBIC DRUG with fine particle SIZE in capsule results in a decreasing porosity of the powder to the fluids outside. Thus it decreases the PENETRABILITY of the solvent into the powder. This results in clumping of the particles.

The correct option is (a) ARM > thigh > buttocks

To elaborate: The DECREASING order of the BLOOD flow to the MUSCULAR tissue is in the order Arm > thigh > buttocks. The blood flow rate is a rate-limiting step in the absorption of drugs from i.m. sites. Most rapid absorption is from deltoid muscles and slowest from the gluteal region.

Correct choice is (c) The speed at which the stomach contents EMPTY into the intestine

Explanation: GASTRIC emptying rate is the speed at which the contents of the stomach contents empty into the small intestine. TIME taken for HALF of the contents in the stomach to empty is known as gastric emptying t1/2.The time required for the gastric contents to empty into the small intestine is known as gastric emptying time.

Correct answer is (a) Folds of the intestinal mucosa

Easiest EXPLANATION: The fold of the intestinal mucosa is KNOWN as the folds of KERCKRING. This result in a 3 fold increase in the intestinal surface area. The surface of these folds possesses finger-like projections known as villi. The surface of villi, from each absorptive CELL several microvilli protrudes thus increasing the surface area 6000 times.

The correct CHOICE is (c) The STRATUM corneum

The explanation: The principal barrier to the ENTRY of XENOBIOTICS is the most superficial LAYER of the epidermis called the stratum corneum. It is composed of dead, keratinized, metabolically inactive cells. It acts as a major rate limiting barrier to passive diffusion of the drugs.

Correct option is (d) 600 TIMES

Easiest explanation: The surface of villi protrudes to several small projections known as MICROVILLI. About 600 projections come up from each absorptive cell that lines the WALL of villi. Thus it INCREASES the surface area to about 600 times.

Correct option is (a) True

To EXPLAIN: Volume of injection and drug concentration matters a lot for absorption and bioavailability. A drug in concentrated injection and LARGE volume is absorbed faster than when given in the dilute FORM and small volume.

Correct answer is (c) Presented a LARGE surface AREA of OIL to the GIT for the ABSORPTION of the drug

The explanation is: Emulsion dosage form is superior to suspensions in administering the lipophilic drug into the body. This is because the emulsion dosage form PROVIDES a large surface area of oil to the GIT for the absorption of the drug.

Right answer is (c) NSAIDs

To EXPLAIN: PULMONARY administration ROUTE is having been limited for administering DRUGS that affect pulmonary systems such as bronchodilators, anti-inflammatory STEROIDS, and anti-allergic. Lipid soluble drugs are absorbed by passive diffusion.

The correct answer is (c) Drug placed under the TONGUE

For EXPLANATION: When the drug is placed under the tongue, we CALL it sublingual administration. When the drug is placed between the cheek and the gum, we call it the buccal ROUTE.

The CORRECT choice is (c) By taking the drug after FOOD

Explanation: Gastric emptying TIME can be delayed by administering food. Since the gastric content without being fluid with particle SIZE below 2MM cannot enter the intestine through the pylorus. Thus it increases the time of gastric emptying.

Correct CHOICE is (B) False

Easy explanation: Powders and granules are administered in HARD gelatin capsules. And viscous FLUIDS and oils are administered in soft ELASTIC shells.

The correct answer is (b) Usage of more BINDING agent

To elaborate: Agglomerative phase of COMMUNICATION is a recent process which involves grinding the drug in a ball mill for a long time to affect spontaneous agglomeration. The tablets so produced were stronger and showed rapid dissolution in comparison to tablets made by another method. It GAVE an increased internal surface AREA of the granules prepared by APOC method.

The correct choice is (c) Mucopolysaccharides

Explanation: The ENTIRE GI tract is LINED by mucus or mucopolysaccharides. It acts as an IMPERMEABLE barrier to the particles such as that of bacteria, cells or FOOD particles protecting our body from harmful organisms.

Right answer is (c) Increase the cost due to more ADDITIONAL processing

To explain I would say: limitation of wet granulation method is Formation of Crystal Bridge by the presence of liquid, the liquid may ACT as a medium for AFFECTING chemical reactions such as hydrolysis, and the drying step may harm the thermolabile DRUGS.

The correct answer is (b) PSEUDOPOLYMORPHS

The explanation is: Stoichiometric type of adducts of the solid where the solvent molecules are incorporated into the crystal LATTICE of any solid are known as SOLVATES. The solvates that can EXIST in DIFFERENT crystalline forms are known as pseudopolymorphs. The phenomenon is known as pseudopolymorphism.

Right option is (d) Solubility, PARTICLE size, polymorphism, SALT FORM, pseudopolymorphism, complexation, wettability

To explain: The various Physicochemical properties of the drug that affect drug dissolution and its rate are Solubility, particle size, polymorphism, salt form, pseudopolymorphism, complexation, wettability, etc. DOSAGE form factors include FORMULATION factors and excipients in the formulation.

Correct answer is (a) Disintegration

Easiest explanation: The solid dosage FORM at first disintegrate into smaller granules or aggregates. Those are then deaggregated to form fine particles. In dissolution, the DRUG is in the solution form and then it GETS ABSORBED.

Right answer is (a) True

The explanation is: The proportion of BINDERS in any TABLET formulation is very critical. INCREASE in the amount of binders TENDS to increase the hardness and decrease the DISINTEGRATION and dissolution rates of the tablet.

The correct choice is (d) 5-8

Explanation: The PH RANGE of the intestine (DUODENUM to the COLON) is anywhere between 5-8, this allows the drugs to get easily absorbed and digested. The small intestine SPECIFICALLY has a pH ranging from 6 to 7.5.

Correct CHOICE is (d) Danckwert’s model

For explanation: Danckwert did not approve the existence of the stagnant layer and suggested that turbulence in the dissolution medium EXISTS at the solid/liquid INTERFACE. Due to which the agitated fluid consists of a macroscopic MASS of eddies or packets reach the solid-liquid interface due to the eddy CURRENTS, absorb the solute by diffusion and carry it to the bulk of the solution.

Right choice is (a) Dissolution rate PER unit area

The explanation is: ACCORDING to the INTERFACIAL barrier model, an intermediate concentration exists at the interface which is a result of the solvation mechanism and is a function of SOLUBILITY. Here in the equation G stands for dissolution rate per unit area, Ki stands for effective interfacial transport constant.