Liquid Syrup Types and Manufacturing Process

The syrup is a Liquid Dosage form generally taken orally. The liquid syrup is manufactured by adding or mixing API with other ingredients and finally packed in a syrup bottle to dispense.

Syrup Definition: Syrup is a concentred or saturated solution of sucrose and Purified water. According to IP and USP concentration of sugar is around 66.7% w/w and 85% w/v.

Types of Syrups:

1. Simple syrup
2. Medicated syrup
3. Flavored syrup

1. Simple syrup: Simple syrup is made by adding sucrose into purified water.

Concentration: To manufacture simple syrup add 66.7 grams in 100.0 gram purified water as per IP, and Add 85 grams in 100 ml purified water as per USP.

2. Medicated syrup: Medicated syrup contains API (Active Pharmaceutical ingredients) with their excipients.

3. Flavoured syrup: Flavoured syrup mainly contains aromatic or flavored excipients are called Flavored syrup.

Advantages of Syrup:

• Simple syrup is used as a preservative because it reduces bacterial and fungal growth due to high osmotic pressure.
• Sugar syrup also acts as an antioxidant by hydrolyzing sugar into sugar laevulose and dextrose.
• Syrup also acts as palatable because it reduces the mask and bitter taste.
• The liquid syrup is easy to manufacture at a low cost.

The disadvantage of Syrup:

• Delay onset of action
• Not suitable for emergency
• Not convenient with gastrointestinal disorders
• Can not avoid first-pass metabolism.

Syrup Preparations Methods:

1. Simple solution method: This method is used for non-volatile and heat-labile materials or active substances.

Heating Method: It is manufactured by adding the required amount of sugar with purified water and heated until it gets a clear viscous solution.

Agitation without Heating: This type of process is used when related active materials are volatile and heat sensitive. Sucrose and other excipients are added to dissolve into purified water. through the agitation process. for eg. sulfate USP syrup.

2. Percolation: Percolation is also called the cold manufacturing process. Sucrose is placed inside a percolator ( cylindrical in shape) before the cotton roll and then purified water is passed through sucrose by adding a small volume continuously. finally Dissolved API is passed.

3. Addition of medicated syrup: In this method, The active substances or fluid extract or tincture are added to the syrup. addition of substances by this process may cause precipitation of alcohol-soluble materials due to dilution. so to avoid problems first add fluid extract or tincture with water and allow the mixture to stand to separate out insoluble constituents, then filter and add sucrose into the filtrate. eg. Aromatic Eriodictyon syrup NF is prepared by using this process.

Note: This process is only used when the insoluble materials are not active ingredients.

Formulation of Syrup:

The syrup is manufactured by adding a suitable vehicle with API.

1. Vehicles: syrup is prepared by using purified water.

2. Excipients:

a) Stabilizers like glycerin, sorbitol, and propylene glycol are added in the required quantity to prevent the crystallization of sucrose. surfactants are used to dissolve ingredients in syrup to get a clear solution.

b) Coloring agents like coal for dyes ( amaranth, tartrazine, and green s) to give color to syrup.

c) Flavouring agents: Flavouring agents are used to enhance the flavoring properties of syrups. eg. like tincture lemon, ginger, wild cherry, vanilla, and orange.

Stages of Manufacturing Liquid syrups:

Dispensing and Weighing: First Dispensing of Materials to be done and transferred to Production areas after weight as per given in BOM (Bill of Material).

Production Tank: The production Tank is used to mix the materials. The sugar tank, syrup manufacturing tank, and storage tank are connected with each other with the dedicated pipeline to transfer the materials. The sugar tank is used to melt the sucrose, where the manufacturing tank is used to mix all ingredients, and the storage tank is used to store the final manufactured materials. storage tank outlets are used to transfer the liquid syrup to the filling machine.

Filtration: Filteration is done to remove the precipitated materials.

Storage Tank: is used to store the filtered solution.

Filling Area: Filling machine is used to fill liquid solution into the pre-cleaned bottle and finally packed into a carton, and corrugated box.

Storage of syrup:

The syrup is generally stored in a dried, and dark cool place below 25°C.