Question

The instructions on an Alka-Seltzer container indicate that the tablet should be added to water and then ingested. Explain why it might be ill advised to chew the tablets

*Please type your answer so I can read it*

Answer 1

Ans. The active ingredients of Alka-Seltzer are sodium bicarbonate (NaHCO₃), anhydrous Citric acid and Aspirin (in some types). Aspirin does not cause any trouble to the oral cavity during chewing.

However, chewing the tablet may cause following problems to oral cavity-

I. The anhydrous citric acid, when dissolved in saliva, would release H⁺ into saliva making it acidic. So, the citric acid is most likely to corrode the oral cavity. Therefore, chewing must be avoided.

II. When in contact with aqueous environment of saliva, citric acid and sodium bicarbonate react together and release CO₂ gas through effervescence. The effervescence gives a fizz feeling in oral cavity. So, fizzing may give uncomfortable feeling during chewing. So, chewing is not suitable.

# Therefore, chewing the tablet MUST BE AVOIDED.

# Why to dissolve in water before ingestion:

Besides the reasons #I and #II explained above, the tablet is dissolved in water to make an instant solution of the ingredients. So, when ingested in liquid form, the ingredients are readily available for absorption in the GIT. Therefore, the uptake of active molecules in the GIT is instant and rapid- thus, it provides faster relief.

# If the tablet is taken in solid form (say, the tablet is swallowed with water), the active ingredients are not directly available for absorption in GIT. The tablet would gradually dissolve in some time and the active molecules would be available in small quantities over prolonged time. In such case, absorption of small quantity of the active drug molecules would not give instant relief.

Therefore, the tablet should be dissolved in water before ingestion for instant relief.