MISCELLANEOUS COMPOUNDS

UNIT-4

SYLLABUS

• Expectorants - Potassium Iodide, Ammonium chloride*
• Emetics - Copper Sulphate, sodium potassium tartarate
• Haematinics - ferrous sulphate, ferrous gluconate
• Poison & Antidote - Sodium nitrite, Sodium thiosulphate, Activated charcoal
• Astringents - Zinc sulphate, Potash Alum.

EXPECTORANTS

• These are those agents/drugs which are used to expel sputum (mucus + cell debris + foreign particles) from the respiratory tract and helps in the treatment of cough.

• These agents are used to clear thick mucus from the respiratory tract including lungs, bronchi and trachea, and providing relief from respiratory tract disorders.

Classification : Based on the mechanism of action, it is mainly

classified into two types:

1. Secretion Enhancers : They mainly give their function by increasing the bronchial secretion of mucus, which dilute the sputum and helps in its removal.

   • e.g. Guaifenesin $\rightarrow$ most common, Potassium Iodide and Ammonium chloride*.

2. Mucolytics : They mainly give their action by breaking the mucus and reduce its viscosity with the action of enzymes.

   • e.g. Bromhexine, Ambroxol etc..

POTASSIUM IODIDE

• Molecular formula: $KI$
• Molecular weight: $166 \text{ g/mol}$

Method of Preparation :

1. It is prepared by treating potassium bicarbonate with hydrogen iodide, which results in the formation of $KI$.

2. It is also prepared by treating hot aqueous solution of potassium hydroxide with iodine.
   $$6KOH + 3I_2 \rightarrow 5KI + KIO_3 + 3H_2O$$

Properties :

• It is an odourless, transparent with saline bitter taste.
• It is soluble in alcohol, water and glycerine.
• It is hygroscopic in nature.

Uses :

• It is used as an expectorants.
• It is also act as a source of potassium and iodine.
• also used as reagent in pharmacy.

AMMONIUM CHLORIDE

• Molecular formula: $NH_4Cl$
• Molecular weight: $53.50 \text{ gm/mol}$

Method of preparation :

Properties :

• It is a colorless/white, crystalline / course powder.
• It is odourless with saline taste.
• It is freely soluble in water and glycerine, but sparingly soluble in alcohol.
• It is slighty hygroscopic.

Reactions : $$NH_4Cl + H_2O \rightarrow NH_4OH + HCl$$

Assay : Currently, acid-base titration is preferred for the assay of ammonium chloride.

• Weight $0.1 \text{ gm}$ of $NH_4Cl$ & dissolve in $20 \text{ ml}$ of $H_2O$.
• Now, add a mixture of previously neutralized formaldehyde solution ($5 \text{ ml}$) & stand by for two minutes.
• Now, titrated against $0.1 N \ NaOH$ solution, using phenolphthalein as an indicator.
• End point is the appearance of pale pink color.
• Each ml of $0.1 N \ NaOH = 0.005349 \text{ gm}$ of $NH_4Cl$.

Uses :

• It is used as expectorants.
• It is also used as acidifiers to maintain acid-base balance.
• It also act as diuretics.

Storage : It is stored in tightly closed container.

EMETICS

• These are those drugs which helps in emptying the stomach by inducing vomiting.
• These are those drugs which induce vomiting.
• Vomiting is the forceful expulsion (out) of gastric content from the body through mouth.
• They are mainly used in the case of:
  • poisoning
  • overdose of any drugs
  • Adverse effects
  • wrong medications. etc..

Mechanism :

1. Emetics stimulates the chemoreceptor trigger zone (CTZ) present in medulla oblongata, which stimulates vomiting centre (VC) and induce vomiting. e.g. morphine, digitalis etc..
2. By irritating the GIT, which increase secretion & movement. e.g. zinc sulphate, Copper sulphate, sodium chloride etc.

Characteristics :

• It should be non-toxic.
• Non interactive with other drugs.
• non-irritant.
• short onset of action.

Examples : Copper sulphate, sodium potassium tartarate

1. COPPER SULPHATE *

It is present in hydroform and also known as blue vitriol.

• Molecular formula : $CuSO_4 \cdot 5H_2O$
• Molecular Weight : $159.6 \text{ g/mol}$

Method of preparation :

Properties :

• It occurs as deep blue color crystals or blue powders.
• It is odourless.
• It is soluble in water and insoluble in alcohol.

Reactions : Copper sulphate and potassium iodide reacts together to form unstable cupric iodide. $$2CuSO_4 + 4KI \rightarrow 2CuI_2 + 2K_2SO_4$$

ASSAY :

• A suitable amount of copper sulphate is weighed and dissolved in water.
• $KI$ and acetic acid are added in this solution.
• Now, iodine ($I_2$) is obtained, which is then titrated with standard sodium thiosulphate solution, using starch as an indicator.
• Titration continues until the blue color disappears.

Uses :

• It is used as emetics.
• It is also used as astringent and a fungicide.

SODIUM POTASSIUM TARTARATE

It is also known as rochelle salt.

• Molecular formula: $C_4H_4KNaO_6 \cdot 4H_2O$
• Molecular weight: $210.158 \text{ g/m}$

Method of preparation : It can be prepared by neutralising a solution of sodium carbonate with potassium bitartrate.
$$2KHC_4H_4O_6 + Na_2CO_3 \cdot H_2O + 6H_2O \rightarrow 2KNaC_4H_4O_6 \cdot 4H_2O + CO_2 \uparrow$$

Properties :

• white/colorless crystalline powder.
• odourless.
• saline taste.
• soluble in water.
• Insoluble in alcohol.

Uses :

• used as emetics.
• also used as saline cathartics.

HAEMATINICS

• These are those drugs or agents which are used to increase the concentration of Haemoglobin (Hb) or iron in blood.
• They are basically used in the treatment of anaemia or Iron-deficiency anaemia.
• These agents are mainly used for the formation of blood.
• Anaemia is a condition of decreased amount of haemoglobin/blood in our body, or mainly loss of RBCs.

Causes :

1. Blood loss (acute/chronic). $\rightarrow$ trauma, haemorrhage etc..
2. Decrease in RBC formation. $\rightarrow$ Hb, Iron.

Examples : ferrous sulphate, ferrous gluconate

FERROUS SULPHATE

• It is used as haematinic and contain $20\%$ Fe. It is also known as green vitriol.
• Molecular formula: $FeSO_4 \cdot 7H_2O$
• Molecular weight: $278 \text{ g/mol}$

Preparation :

• It is prepared by treating iron with dil. sulphuric acid, which forms ferrous sulphate and liberated $H_2$ gas.

Properties :

• It is pale, bluish green crystals or granules.
• It is odourless and bitter saline taste.
• It is soluble in water and insoluble in alcohol.

Chemical reactions :

• On heating, it decomposed into sulphur dioxide, sulphur trioxide and ferric oxide salts. $$2FeSO_4 \xrightarrow{\Delta} Fe_2O_3 + SO_2 + SO_3$$

Assay :

• It is assay by redox reaction.
• $1 \text{ gm}$ of ferrous sulphate is weighed and dissolved in $20 \text{ ml}$ of dil. $H_2SO_4$. (also used as indicator in this).
• The resultant solution is titrated with $0.1N \ KMnO_4$.
  $$10FeSO_4 + 2KMnO_4 + 8H_2SO_4 \rightarrow K_2SO_4 + 2MnSO_4 + 5Fe_2(SO_4)_3 + 8H_2O$$

Uses :

• It is used as haematinics.
• It is also used for treating anaemia (iron - deficiency anaemia).

FERROUS GLUCONATE

• Molecular formula: $C_{12}H_{22}FeO_{14} \cdot 2H_2O$
• Molecular weight: $482.18 \text{ g/m}$
• It contains about $12\%$ Fe (iron).

Method of preparation :

• Freshly prepared ferrous carbonate is heated with suitable concentration of gluconic acid in aq. solution to produce ferrous gluconate.

Properties :

• It is yellowish grey powder.
• It have burnt sugar odour.
• It is soluble in cold water and insoluble in alcohol.

Uses :

• It is formulated in tablet dosage form in case of iron deficiency anaemia.
• It is also used in elixir form.
• used as haematinics.

POISON AND ANTIDOTE

• Poison is any substance that cause illness in body or even death after administration in body.
• Poison is administered due to:-
  1. Intentional $\rightarrow$ when sometime cause to harm himself/herself.
  2. Unintentional $\rightarrow$ sometime people administered it accidentally.

Symptoms :

• Breathing Problem
• Decreased heart rate
• Dilated pupils
• Vomiting, Diarrhoea

ANTIDOTES

• These are those substances which are used to neutralize the effect of poison.
• These substances are mainly used in the treatment of poisoning.

Classification/Types :

On the basis of mechanism of action, classified into three categories:

1. Mechanical Antidotes :
   • These are those antidotes which prevent the poison from getting absorbed into the body.
   • e.g. activated charcoal.
2. Physiological Antidotes :
   • These are those antidotes which produce the opposite/reverse effect of poison.
   • e.g. Sodium Nitrite.
3. Chemical Antidotes :
   • These are those antidote which alter/change the chemical nature of poison, which convert the poison into inactive or harmless compound.
   • e.g. Sodium thiosulphate.

MECHANISM :

e.g. Cyanide poisoning.

• Normally, during cellular respiration Cells take $O_2$ from blood with the help of enzyme Cytochrome oxidase.
• with the help of $O_2$ Cells generate ATP, Energy.

SODIUM THIOSULPHATE

It is also known as sodium hyposulphate. It contains not less than $99\%$ and not more than $100.5\%$.

• Molecular formula: $Na_2S_2O_3 \cdot 5H_2O$
• Molecular Weight: $248.18 \text{ g/mol}$

Method of preparation :

Properties :

• It is colorless, transparent crystals having a bitter salty taste.
• It is soluble in water and insoluble in alcohol.

Chemical reaction :

Assay :

• It is assayed by redox titration.
• Take about $0.5 \text{ gm}$ of dried sodium thiosulphate.
• Dissolved it in $30 \text{ ml}$ of water.
• The resultant solution is titrated with $0.1 N$ iodine solution.
• using starch as an indicator.
• titration is continues until blue color of solution disappears.
• Each ml of $0.1 N \ Iodine = 15.81 \text{ mg}$ of $Na_2S_2O_3$.

Uses :

• Used in the treatment of cyanide poisoning with sodium nitrite.
• also used as antioxidants, topical antifungal agents.
• also used to treat skin infections.

ACTIVATED CHARCOAL

• It is the residue obtained from the destructive distillation of various organic material.
• It is prepared by using various organic wastes such as sucrose, lactose, rice, starch, coconut etc.
• They give their work by using its absorptive power.

Properties :

• It is fine, black, Odourless and tasteless powder.
• It is insoluble in water and other Organic solvents.

Medicinal uses :

• It is used as an emergency antidote in many forms of poisoning.
• It will adsorb alkaloids, $NH_3$, $CO$, $CO_2$, $O_2$, $N_2$, $NO_2$ and etc.
• It is also used in filters of gas masks.

ASTRINGENTS

• These are those substances which cause protein precipitation.
• These agents are applied topically on damaged skin, mouth and mucous membrane of gastrointestinal tract which forms a protective layer.

Mechanism :

• Astringents forms the protective layer which:-
  • protects against bacteria and infections.
  • prevents capillary leakage when applied to bleeding areas.
  • reduces local oedema, exudation, inflammation and mucus secretion.
• They also reduces the cell permeability because of their capability of precipitating proteins.

Examples : Zinc sulphate, Potash Alum etc..

ZINC SULPHATE

It is also known as white vitriol.

• Molecular Formula: $ZnSO_4 \cdot 7H_2O$
• Mol. Weight: $287.54 \text{ g/mol}$

Preparation :

Properties :

• It is colorless, transparent or crystalline powder.
• It is odourless & metallic taste.
• soluble in water & glycerine, insoluble in alcohol.

Uses :

• used as astringents.
• also used as an antiseptic.
• also used for treating acne, dandruff.
• orally administered for healing wounds.

POTASH ALUM

It is also known as potassium aluminium sulphate.

• Molecular formula: $KAl(SO_4)_2 \cdot 12H_2O$
• Molecular weight: $474.4 \text{ g/mol}$

Preparation :

Properties :

• It exists as colorless, transparent or granular crystals.
• sweet astringent taste.
• soluble in water and insoluble in alcohol.

Medicinal uses :

• used topically as astringents.
• also used as antiseptic.
• also used as pharmaceutical aid.