What is the difference between syrup and suspension?

What is the difference between syrup and suspension?

The Syrup is a liquid dosage forms that contains a medication dissolved in a sweet liquid, such as sugar or sorbitol solution. The syrup is typically used to treat coughs, colds, and sore throats. It is also used to deliver medications to children who have difficulty swallowing bitter pills. The syrup is easy to take and has a sweet taste, which makes it more pleasant for children.

Suspension is a liquid dosage form that contains Active pharmaceutical ingredients (APIs) mixed with a small number of solid particles. The solid particles are insoluble in liquid, so some parts of them remain suspended in the liquid. Suspensions are typically used to deliver medications that are insoluble or poorly soluble in water. Suspensions may be cloudy or opaque, and they may need to be shaken before use to ensure that the medication is evenly distributed.

FeatureSyrupSuspension
AppearanceClear and colorlessCloudy or opaque
TasteSweetMay be bitter
Ease of useEasy to takeMay need to be shaken before use
Intended useCoughs, colds, sore throats, childrenMedications that are insoluble or poorly soluble in water
What is the difference between syrup and suspension

What is the difference Between Syrup and Suspension?

Syrup and suspension are two liquid medications, with solution and emulsion being the other two main dosage forms. Solution and syrup are the same thing, but syrup is the more common term in many countries. Suspensions contain small particles that must be shaken before use, while solutions are clear and do not need to be shaken.

What is Syrup?

The syrup is a form of liquid oral medicine that contains sugar or a sugar substitute (like sorbitol), flavoring agents, and APIs. The use of sugar in syrups is mainly for improving its taste and to improve the solubility properties of the medicine, because sugar has highly soluble properties like Propylene Glycol. Syrups can be manufactured with some natural ingredients, herbal medicines, or synthetic ingredients. Syrups may be colorless or have some distinct color as per marketing requirements.

Syrups are used to treat coughs colds, allergies, and many respiratory infections in adults. 

According to the US Pharmacopeia syrup is a solution of Sucrose in Purified Water. It contains a preservative unless it is used when freshly prepared. When 850 gm of sucrose is dissolved in purified water and the volume of solution is made up to 1000 ml that is a saturated solution of sucrose.

Otherside, Indian Pharmacopeia gives another definition of syrup, it describes syrup as “a homogeneous mixture of solute in liquid is known as syrup”. In solution or syrup is a pre-dissolved solute in a solution before being administered as a medication. In IP 667 gm of sucrose dissolved in sufficient purified water to make it 1000 ml is called a saturated syrup.

In the syrup formulation, the drug content is equally distributed throughout the whole volume of the container. There is no need to shake the bottle before taking the dose of the syrup.

Syrups/ Solutions primarily are manufactured in sugar or sorbitol base which is also known as syrupy base. Higher the concentration of sugar or sorbitol is the signal of improved quality and taste of the syrup. In general, 20% to 50% of sugar is used in the base of commercial medicines in the Indian and US markets. A suitable flavor is also added to the syrup to improve its taste and acceptability. 

In syrup, sugar concentration also helps to keep safe from microbiological growth in the syrup. 

Examples of syrups

Cough syrups are usually syrups in nature and are a good example of homogeneous mixing of drug content in the medium. Mucinex, Chestal, Dayquill, Robitussin, Chericoff, Ftox-DX, Cozicof syrup, etc are also syrups in nature. 

Types of Syrups

In the pharmaceutical industry, there are several types of syrups that may include:

  • Simple syrup: It is a base for different other syrups that contain equal parts of sugar and water. 
  • Medicines syrups: Medicated syrups contain sugar, water, and Active Pharmaceutical Ingredients such as cough suppressants, expectorants, antihistamines, and vitamins. 
  • Compound syrups: These syrups contain more than one therapeutic agent or multiple APIs in one syrup, these syrups are formulated to treat multiple symptoms. In India, Fixed dose combinations are a true example of compound syrups.

Syrup Pros:

  • Syrups are the best dosage of drug medium for children because they can not swallow tablets and capsule forms.
  • Syrups are more homogeneous in the concentration of drugs than suspensions.
  • These are easy to swallow due to their sweet in taste.
  • Syrups are more instant drug release medium than other dosage forms like tablets and capsules.

Cons:

  • Syrups are expensive drugs to transport anywhere in respect of tablets and capsules.
  • The manufacturing cost of syrups is higher than suspension.
  • Syrups are not safe for diabetes patients due to they contain high amounts of sugar.
  • Syrups with unpleasant taste can cause vomiting in patients. 

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What is Suspension?

A suspension is a type of liquid oral medicine that contains solid particles of API, it has a liquid base and has suspending agent that protects solid particles to settle them at the bottom. Suspension is used to treat various diseases such as infections, coughs, colds, allergies, and many more conditions. Usually, suspensions are cloudy or opaque in appearance rather than clear and transparent as syrups. They have some suspending particles that make them cloudy and opaque. 

Suspension is a liquid dosage form that is usually similar to syrups in physical appearance but different in nature and properties. 

Suspension can have some insoluble drug molecules mixed in so prior to the use of any suspension it is always advised to shake the bottle well so that each portion of the suspended drug gets mixed properly. After shaking the suspension the chances of uniformity of content increase.

In the suspension, the distribution of content does not remain the same when it is kept for a long time, the bottom layer of suspension becomes more concentrated than the top layer of liquid. Is very common in suspension a light-colored layer is seen on the top side of a bottle. 

Types of suspensions

  • Usually, antibiotics for pediatric use are prepared in suspension form, which is directed to mix in water before use, they are good examples of a suspension.
  • Antacids are also in suspension nature because they are not soluble in water and sugar. 
  • Some more examples of suspension are Aceclofenac and Paracetamol suspension, Promethazine, and Paracetamol suspension. 
  • Topical suspensions are applied to the skin and used for some dermatological conditions. 

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Pros: 

  • Suspensions are an easy-to-swallow dosage form for infants and children who can not swallow solid dosage forms of medicines.
  • The cost of manufacturing is lower than syrups.
  • Suspensions are easy to swallow for those who can not swallow capsules or tablets.

Cons:

  • The uniformity of content in suspension is not of the level of syrups.
  • Segmentation of drug content is very common in suspension. 
  • The taste of suspensions never becomes as syrupy.
  • Suspension may have an unpleasant taste that can cause vomiting.

Conclusion

The main difference between syrups and suspensions exists in composition, use, properties, and purpose of preparation. Syrups are more tasty oral medicines than suspensions, syrups are made of sugar or sugar substitutes, while suspensions are liquid medicines that may contain sugar in their base but in less portion than syrups, they are usually palatable-based medicines. 

In the pharmaceutical industry, it is well known that syrup and suspension are two different types of dosage forms but for the common man, these two things are similar and just liquid oral medicines. Syrups and suspensions are manufactured in the same section in a company but these two are slightly different in nature, quality, and characteristics. The difference between syrup and suspension is elaborated conclusively here.

References

  • USP- Pharmacopeia-USP29-NF24 Page 3447
  • Indian Pharmacopeia-2014
  • What Is an Active Pharmaceutical Ingredient (API)?[verywellHealth]
  • Oral Solutions and Suspensions (8/94)[FDA(.gov)]