1 Dubai Pharmacy College for Girls, Dubai, United Arab Emirates
Corresponding author details:
Aliasgar Shahiwala, Professor
Dubai Pharmacy College for Girls
Dubai,United Arab Emirates
© 2019 AlAteib NA, et al. This is
an open-access article distributed under the
terms of the Creative Commons Attribution 4.0
international License, which permits unrestricted
use, distribution, and reproduction in any
medium, provided the original author and source
are credited.Vium mor li, poracidisus es condam
Improving patient compliance with significant therapeutic value is highly important
to be in concern while developing an oral dosage form. Undesirable taste of the drug can
influence patient compliance and product quality. Health care providers are dealing with
bitter drug issues while orally administering to each pediatric patients and elderly patients.
Masking the unpleasant taste of bitter drugs is a potential tool for the enhancement of
patient compliance and success of the product. Various approaches and methodologies of
development for masking the undesirable taste of drugs with consideration of applications,
evaluations, and technologies for taste masking. This review covers the factors need to be
considered for taste masking, different taste masking approaches and recent technologies
developed for taste masking. The brief overview provided in this review will helps readers
to explore further in a particular aspect of their interest.
Taste masking, Inclusion complexes, Resins, Microencapsulation
Pediatrics and elderly patients specifically; are difficult to control while administering
the unpleasant taste of specific drug, leading to administer fewer doses, which cause
less efficiency. Taste masking is the proper way to improve the quality of the treatment
. The taste masking defined as a perceived decrease of an unpleasant taste of active
pharmaceutical ingredients . There are several applications and methodologies of
taste masking, and each method has specific advantages. The easiest method involves
the use of flavor enhancers and in case no results found with this method, then complex
methodologies comes on the board. The techniques found to be effective on taste masking
are; inclusion complex formation with cyclodextrin, ion exchange resins, granulation,
liposome, microencapsulation, multiple emulsions, prodrug approach, polymer coating,
solubility limiting methods, and the use of anesthetic agents . Then evaluation of the
taste masking is essential, such as evaluation of liquid and solid dosage forms, evaluation of
microspheres, recent innovations, recent trends (AdvaTab ODT Technology), recent trends
(Microcaps ODT Technology), liquitard ODT Technology, for multiplex and formulcoat, and
linecaps. Moreover, a recent innovation tastes masking by using electronic tongue.
Strongly bitter taste medicines have the ability even with the least exposure; to perceive
the bad taste. The optimum efficient technology for strong bitter drugs is coating, nevertheless,
it reduces the efficiency of the technique. Moreover, microencapsulation of a potent bitter drug
is not enough to provide the taste masking of liquid oral suspensions [4,5].
As the dose is small, it is easy to mask the taste of the specific medicine with the
flavoring agents. While in the case of high doses required, flavoring agents may fail to mask
the taste. An ideal taste masking is coating with sweeteners for the suitable final dosage
form size [1,4].
The characteristics of the drug can reduce the efficiency of the taste masking. For
instance, when the shape of the drug is irregular, taste masking will be insufficient and less
effective. Moreover, the small particle size as well can affect the taste masking overcome
The simplest approach for masking the taste of active pharmaceutical ingredients is using flavors, sweeteners and amino acids technique. While in the case of highly bitter drugs, this technique is not effective enough. The importance of using taste masking techniques with artificial sweeteners is to improve the efficiency of the techniques. An excipient such as flavors, act by enhancing the formulation with better taste. Example of flavors is; menthol and bitterness inhibitors. An additional excipient is sweeteners such as Sucrose, Glucose, Fructose, Sorbitol, Mannitol; and they are highly water soluble dissolving in saliva with coating the taste buds [6-8].
The best technique for taste masking is a polymer coating, due
to its acts as a physical barrier to the drug particles, which result in
minimizing the interaction between the drug and the taste buds. The
various polymer coating can be as hydrophobic polymers, hydrophilic
polymers, lipids, and sweeteners [6-8].
Usually, the formation of inclusion complex method is used when
low dose drug is required. This technique works by the host and
guest link, where the host is the complexing agent; and the guest is
the active moiety. The purpose of the complexing agent is to mask the
unpleasant taste of specific drug either by reducing its oral solubility
or reducing the amount of the drug particles to taste buds. The most
common use complexing agent is cyclodextrin, due to its sweet in
taste, non-toxic, and cyclic oligosaccharide acquired from starch.
In inclusion complexes, the Vander Walls forces are predominantly
The ion exchange resins groups have the ability to exchange
charge counter ions, therefore absorbing the ions into the polymer
matrix. They are high molecular weight water insoluble polymers
and synthetic organic polymers containing a hydrocarbon chain.
According to the taste masking, it depends on the nature of drug
whether weak cation exchange; such as carboxylic acid moieties
or weak anion exchange; such as predominantly tertiary amine
Dispersion of one or more active ingredients; in an inert carrier
of solid state prepared by the melting-solvent method is known as
a solid dispersion. This technique is used for masking the bitter
drug taste with the help of polymers, sugar, and other suitable
agents. Various carriers are used in a solid dispersion method;
consist of ethylcellulose, hydroxypropyl methylcellulose, mannitol,
polyethylene glycols, povidone, and urea [5-8].
The method of coating active pharmaceutical ingredients
either solid or liquid droplets with a polymeric material; is called
Microencapsulation. There are various types of coating agents such as;
beeswax, carnauba wax acrylics, ethylcellulose, gelatin, hydroxyethyl
cellulose, povidone, and shellac. By using Microencapsulation
method, different techniques are used for achieving taste masking;
such as phase coacervation, polymerization, solvent evaporation, and
Masking the bitter taste of the drug using multiple emulsions
technique is a good approach. This technique is achieved by dissolving
the active pharmaceutical ingredient in the inner aqueous phase of
w/o/w emulsion. Those are in which internal aqueous phase and the
external aqueous phase are separated by the oil phase. Another type is
o/w/o emulsion, in which water globules are containing oil globules.
The effectiveness of masking the bitter taste using both types of
multiple emulsions of chloroquine phosphate is high. Liposomes are
also good taste masking methods, and they are carrier molecules
containing different layers of lipids; in which the unpleasant taste of
specific drug is entrapped within the lipid molecule. The bitterness of
the active drug can be inhibiting by phospholipids. Different examples of phospholipids; are phosphatidic acid, phosphatidylinositol, soya
Prodrug approach is known as chemically inactive molecules,
but due biotransformation happens to the prodrug, it converts to
the active compound. Prodrug method achieved by changing the
molecular formation of the initial molecule, and the amount of the
unpleasant taste receptor –substrate adsorption can be modified [6-9].
Masking the taste with lipids, oils, polyalcohols, and surfactants;
results in increasing the viscosity which coat the taste buds. While
formulation, a large excess of lecithin substances required to control
unpleasant taste drugs [5-10].
Salt preparation tends to decrease the solubility of the drug by
altering the chemical group which is responsible for the unpleasant
taste. To form an ionized drug molecule, many salts of organic
compounds are formed by addition or by removal of the proton. After
formulation, it neutralized with a counter ion [4,7,10].
Sodium bicarbonate is used to form an effervescence effect
to release carbon dioxide. When the effervescent preparation is
added to water, the sodium bicarbonate reacts with the acid and the
remaining solution known as carbonated water. The drug dissolves
in the carbonated water which helps to mask the unpleasant taste
E-tongue is a multi-channel taste sensor, and it acts as a human
tongue. It provides a fast and simple assessment of oral formulation.
The taste sensor contains a transducer that consists of polymer and
lipid membrane, which act by transforming taste information into
electrical signals of the membrane [11-13].
When the rate of the drug release from microspheres is known,
the index of the degree of taste masking is achieved [11,14,15].
Alpha MOS is a taste analyzing system; that contains a taste sensor composed of silicon transistors with an inorganic coating that manages the selectivity and sensitivity of each sensor. The sensor can approximately last for one year [4,16].
AdvaTab ODT technology is developed by APTALIS Pharmaceutical technologies, which features with high physical stability, stable during package and transport, pleasant taste, and good patient compliance. Also, coating method is used for Microcaps ODT technology. The coating is a polymer membrane which eradicates the unpleasant taste of the drug. There are several advantages with Microcaps ODT technology, such as taste masking in a precise way, good release, and patient . Liquated ODT technology provides an effective, suitable, and taste-masked powder formulation in a single dose sachet; which can be administered as a suspension or sprinkle [4,18].
Formulplex and Formulcoat is another technology that masks
the taste by coating the micro or nano-sized particles with a nonorganic solvent at room temperature [11,18] .KLEPTOSE® Linecaps
technology uses pea maltodextrin for masking the unpleasant taste
of the drug by reducing the total amount of drug particles exposed to
the taste buds [19,20].
Masking the obnoxious taste must be in consideration toenhance
the patient compliance. The aim of the techniques mentioned in the review is to have an effective taste masking. Researches of maskingthe
taste drug delivery system are essential for the treatment quality.
An ideal taste masking technique should have excellent patient
compliance, additionally avoidance of interaction with drug release.
Copyright © 2020 Boffin Access Limited.