Background: Cinnarizine, an antihistaminic drug, is commonly formulated in combination
with domperidone and with paracetamol for treatment and prevention of motion sickness and migraine.
Objective: The aim of this work was to develop new, simple, precise and selective chromatographic
methods (RP-HPLC and TLC-densitometric methods) for the determination of these drugs. These
methods can be used as analytical tools in the routine examination in quality control laboratories.
Methods: The first method was RP-HPLC method, the separation was carried out on an Inertsil® ODS-
3V C18 column (250 mm x 4.6 mm, 5 μm) using a mobile phase composed of methanol: acetonitrile
(45: 55, v/v) at a flow rate of 1ml/min. The detection was carried out at 220 nm. The second method
was a TLC-densitometric method where the studied components were separated using a developing
system composed of toluene: ethyl acetate: methanol: triethylamine (5: 4.3: 0.7: 0.5, v/v/v/v) on TLC
silica gel 60 F254 plates, followed by densitometric scanning at 270 nm.
Results: In RP-HPLC method, the peaks were sharp and well separated, the retention times were 5.25,
3.48 and 2.78 min, for cinnarizine, domperidone and paracetamol, respectively. Linearity was obtained
over the concentration ranges 1-22, 0.75-16 and 25-550 μg/ml, for cinnarizine, domperidone and
paracetamol, respectively. In TLC-densitometric method, well separation and linear relationships were
achieved over the concentration ranges of 0.2-2, 0.15-1.6 and 5-50 μg/spot, for cinnarizine, domperidone
and paracetamol, respectively. Method validation was conducted according to ICH guidelines in
terms of linearity, accuracy, selectivity, precision and robustness.
Conclusion: The developed methods were applied for the determination of the cited drugs in tablets
containing binary drug mixtures. The methods are simple and precise and can be used for routine analysis
of the labelled drugs in combined dosage forms in quality control laboratories.