Advantage And Disadvantage Of Suppository

Suppository is a solid dosage form containing one or more active ingredients and is used to deliver the medication in the body cavities such as the rectum/vagina. It produces local action or systemic absorption of the active ingredients. It may melt at body temperature or dissolved or dispersed on a suitable basis that may be soluble or dispersible in water.

Why suppository

Suppository Base

There are two types of suppository base: lipophilic and hydrophilic suppository. Lipophilic suppositories are fat and wax-based which can be melted according to the human body. The hydrophilic suppository is glycerin-based and requires liquid for dissolution.

Read Also: The Different Types Of Suppository

These suppositories can be composed of, but not limited to, cocoa butter, coconut oil, glycerinated gelatin, hydrogenated vegetable oils and hard fats, polyethylene glycols (PEGs) and fatty acid esters of polyethylene glycol (PEG).

Suppository Shape

Suppositories have classically been cylindrical in geometry, longer than wide, with the most common shape being the ‘bullet’ or ‘torpedo’ shape. However, other commonly used shapes for suppositories include round and elongated ovals, tampon and ‘teardrop’ or ‘cone.'

Mechanism Of Action (MOA) Of Suppository

A suppository will first dissolve in the fluid or melt on the mucous layer depending on whether it is hydrophilic or lipophilic. Due to osmotic effects of the dissolving vehicle, water is drawn to the rectum or vagina, and as the suppository dissolves or melts and spreads, drugs dissolved in the suppository will diffuse out toward the mucosal epithelial surfaces. Drugs suspended in the suppository base will first need to leave the vehicle (if it is water immiscible) under the influence of either gravity or ambulation and then begin solubilizing in fluid. For lipophilic melting suppositories, there is no need for fluid to be present to soften and spread the suppository. As the suppository liquifies under heat, the same drug transport observed in dissolving suppositories will occur in melting suppositories.

Why Use Suppository

Suppositories deliver many types of medication, and a person may need to use them if they:

1. are having seizures and cannot take medicines by mouth

2. are unable to swallow medication for any reason

3. are vomiting and cannot keep pills or liquids down

4. have a blockage that stops the medication moving through the digestive system

People may also take suppositories if the medication:

1. tastes too bad to take by mouth

2. would break down too quickly in the gut

3. could be destroyed in the gastrointestinal tract

Advantage Of Suppository

1. prolongation of drug action

2. biotransformation of drugs in liver, pH conditions and gastrointestinal enzymes are avoided as the portal circulation is bypassed

3. Indomethacin may cause gastric irritation hence these drugs are sometimes administered rectally

4. When oral administration of a drug is not suitable as in infants or patients suffering from nausea, vomiting and gastrointestinal disturbances; suppositories serve as an alternative for drug administration

5. Undissociated drugs are absorbed more rapidly from gastric mucosa than the ionised ones

6. faster onset of action as compared to oral administration

7. The absorption rate of the drug is not influenced by food or gastric emptying

8. Allows achieving rapid systemic effects by giving a drug in a suitable solution (as an alternative to injection), with the additional advantage that such effect can be rapidly terminated in cases of toxicity or overdose

9. Compared to the parenteral drug administration it does not have pain or a site of action-related issues

10. It does not have systemic side effects compared to other dosage forms

11. Total bioavailability can be achieved compared to oral dosage forms

12. The rectal route of administration offers a much more constant atmosphere for the drug to be absorbed than the oral route

Read Also: Types Of Suppository Bases

Disadvantages Of Suppository

1. Not convenient for many people

2. Variable available fluid which can affect absorption

3. Leakage of medication after melting at body temperature

4. Can be affected by disease condition like diarrhea

5. Mucosa irritation