Oral Syrups

The overall processes to develop the three types of syrups , namely solutions, suspensions, and emulsions, are quite similar, so the general process will be described below and differences pointed out as needed. In all cases the Active Pharmaceutical Ingredient, API, is mixed with sweeteners, water, flavors, and other inactive ingredients, and then packaged into bottles and prepared for shipping.


(Copyright GEA Process Engineering Inc., Columbia, MD)

This module describes production equipment used in the syrup manufacturing process. The Quality Control module describes additional equipment used to monitor quality parameters during this process.

Process Map

Oral Syrup Production


The first step in producing oral syrups is combining  the API with the sweeteners, water, flavors, and other inactive ingredients. For solutions, gentle mixing is generally sufficient in helping the ingredients dissolve into the water. Emulsions will typically require high shear mixing to force the water and oil phases to mix properly. Lastly suspensions have different requirements for mixing depending on the specific formulation. Occasionally heat is added to help the sweeteners, typically sugar, dissolve more easily to create the syrup.

Commonly used mixers include tumblers and ribbon mixers. Tumblers are used for their simplicity and ability to operate in batch operations, allowing for more effective quality control. High quality control coupled with the gentle mixing cycles are highly sought after in the pharmaceutical industry. When high shear mixing is required, ribbon mixers are often used for their ability to scrape the outside walls and induce mixing of multiple phases.

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(Copyright Glen Mills, Inc., Clifton, NJ )

Ribbon Mixer.png

(Copyright H.C. Davis Sons Manufacturing Co., Inc., Bonner Springs, KS)


Once the mixing is complete, the oral syrups can be pumped into bottles and sealed for distribution. Typically plastic bottles are used as the container for safety. Pistons are inserted into the bottle and the syrup is pumped into the bottle gently to prevent splashing. After the bottles are filled, a plastic and aluminum seal is added to prevent tampering, the cap is added, and an external seal may also be attached. Since syrups are ingested into the body, sterilization is not required, as the digestive system is capable of handling most microbes.

After packaging, pharmaceutical syrups are tested against product specifications. The Quality Control module describes equipment relevant to this testing process.

Process Map

Oral Syrup Production


GEA Process Engineering Inc. , Columbia, MD

Glen Mills, Inc. , Clifton, NJ

H.C. Davis Sons Manufacturing Co., Inc. , Bonner Springs, KS


Bennett, Bill and Cole, Graham. Pharmaceutical Production: An Engineering Guide. United      Kingdom: The Institution of Chemical Engineers, 2002. Print.

Niazi, Sarfaraz K. Handbook of Pharmaceutical Formulations. Vol. 2. CRC LLC, 2004. Print.

Prism Pharma Machinery “Process.” Web .   “http://www.liquidsyrupmanufacturingplant.com/process.html”

Yuan, Y., Pfizer Inc., personal communications, 2017.


Howard Hsu