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Multiple choice chemistry medicinal chemistry antacids and antihistamines therapeutic action of different classes of drugs ph regulation of the stomach

Which of the following substance is an antacid?

  1. $NaCl$
  2. $Mg(OH) _2$
  3. $HCl$
  4. $H _2SO _4$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
Due to its mildly basic and non-toxic nature, magnesium hydroxide is widely used as an antacid to neutralize stomach acids and prevent indigestion and heartburn. 

It is also used as a laxative, antiperspirant, underarm deodorant, to treat sores, in wastewater treatment, and as a fire retardant.

Therefore, the correct option is B.

Multiple choice chemistry medicinal chemistry antacids and antihistamines therapeutic action of different classes of drugs ph regulation of the stomach

Which of the following is not used as an antacid ? 

  1. Magnesium hydroxide

  2. Sodium carbonate

  3. Sodium bicarbonate

  4. Aluminium phosphate
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

An antacid is a substance which neutralizes stomach acidity and is used to relieve heartburn, indigestion or an upset stomach.

Example- $Mg(OH) _2, Na _2CO _3, NaHCO _3$.
Aluminum phosphate is not used as an antacid.
Hence, the correct option is D.

Multiple choice chemistry medicinal chemistry antacids and antihistamines therapeutic action of different classes of drugs ph regulation of the stomach

The drug cimetidine was designed to:

  1. prevent the interaction of histamine with receptors

  2. stimulates the secretion of pepsin

  3. reduce gaestro intestinal juices

  4. all of the above
Reveal answer Fill a bubble to check yourself
A,C Correct answer
Explanation

The drug cimetidine (Tegamet), was designed to prevent the interaction of histamine with the receptors present in the stomach wall. This resulted in release of lesser amount of acid. The importance of the drug was so much that it remained the largest selling drug in the world until another drug, ranitidine (Zantac), was discovered.

Multiple choice chemistry medicinal chemistry antacids and antihistamines therapeutic action of different classes of drugs ph regulation of the stomach

An antacid tablet weighing 1 g containing aluminium hydroxide as the only basic substance and the rest of its components being neutral, was dissolved in 200 mL of 0.1 M HCI. The excess HCI was back titrated and required  90 mL of 0.1 N base for exact neutralization. Mill equivalents of aluminum hydroxide in the sample of antacid tablet is 

  1. 9

  2. 11

  3. 12

  4. 20
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The total milliequivalents of HCl = 200 mL * 0.1 M = 20 meq. The excess HCl neutralized by 90 mL of 0.1 N base = 9 meq. Therefore, the HCl consumed by the antacid = 20 - 9 = 11 meq. Since aluminum hydroxide is the only base, it must have neutralized 11 meq of HCl.

Multiple choice chemistry medicinal chemistry antacids and antihistamines therapeutic action of different classes of drugs ph regulation of the stomach

Histamine is responsible for the nasal congestion associated with common cold and allergic response to pollen.

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The pollen triggers these cells in nasal chambers, causing them to release histamine and the other chemicals. Histamine dilates the small blood vessels of the nose and fluids leak out into surrounding tissues causing allergy symptoms.

So, the above statement is true.

Multiple choice chemistry medicinal chemistry antacids and antihistamines therapeutic action of different classes of drugs ph regulation of the stomach

Examples of antacids are:

  1. sodium hydroxide

  2. sodium bicarbonate

  3. magnesium hydroxide

  4. urea
Reveal answer Fill a bubble to check yourself
B,C Correct answer
Explanation

Antacids: Tension and mental stress escalate the level of acid in bile juice. This hyperacidity can be combated using bases like calcium carbonate, magnesium hydroxide or aluminium hydroxide in the form of tablets or aqueous suspensions. These react with hydrochloric acid in the stomach and neutralize it partially. Gelusil and Digene are two examples of antacids. Antacids must be basic but not enough to make it caustic. Hence, options B and C are appropriate.

Multiple choice chemistry medicinal chemistry antacids and antihistamines therapeutic action of different classes of drugs ph regulation of the stomach

Urea is responsible for the nasal congestion associated with common cold and allergic response to pollen.

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The pollen triggers these cells in nasal chambers, causing them to release histamine and the other chemicals. Histamine dilates the small blood vessels of the nose and fluids leak out into surrounding tissues causing allergy symptoms.

So, the above statement is false.