Leflunomide is a well-known rheumatoid arthritis drug. The study's main objective was to evaluate the food and drug interaction studies of leflunomide/visible spectrophotometer technology. A previously developed selective, observant, and exact UV spectroscopic approach for quantitative analysis of leflunomide was applied here. Stock solutions of 1 mMole (0.027 g dissolved in 100ml volumetric flask in methanol) were prepared and diluted to concentration ranges of 0.01 to 0.055 mMole using the same solvent for the leflunomide assay. 50 g mL-1 solutions of leflunomide were prepared to study the potential interaction between leflunomide and fruit juices (apple, orange, and grey fruit). Individually, these solutions were diluted in an equimolar ratio and maintained on a water bath at 37±5°C for three hours. The UV/visible spectrophotometer was being used to evaluate these solutions. Although leflunomide and juices remained constant throughout the experiment, the interaction spectra of all juices with the drug showed that the availability of leflunomide was changed in the presence of all juices. In methanol, leflunomide used to have a maximum absorbance in the ultraviolet region at (259nm), but after interaction with fruit juices (apple, orange, and grey fruit), complex formation was indicated by a change in spectrum shape, pattern, and maximum absorbance with an increase in percentage availability (113.90 -139.64%) as the interaction began, λmax shifted to 271 nm. There was a clear interaction between leflunomide and these juices that could change the drug's pharmacological effects. Leflunomide's maximal absorbance in methanol was found to be 259 nm, its spectra changed following interaction with fruit juices, indicating that a complex was formed. Co-administration of these medications should be avoided, as a result.
| Published in | European Journal of Clinical and Biomedical Sciences (Volume 12, Issue 1) |
| DOI | 10.11648/j.ejcbs.20261201.11 |
| Page(s) | 1-6 |
| Creative Commons |
This is an Open Access article, distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution and reproduction in any medium or format, provided the original work is properly cited. |
| Copyright |
Copyright © The Author(s), 2026. Published by Science Publishing Group |
Leflunomide, Methanol, Food-drug Interaction, Absorbance Maxima, Fruit Juices
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APA Style
Shabir, S., Qamar, S. T., Fatima, R., Shaikh, R., Shabir, J., et al. (2026). Studies of Food & Drug Interaction with Leflunomide. European Journal of Clinical and Biomedical Sciences, 12(1), 1-6. https://doi.org/10.11648/j.ejcbs.20261201.11
ACS Style
Shabir, S.; Qamar, S. T.; Fatima, R.; Shaikh, R.; Shabir, J., et al. Studies of Food & Drug Interaction with Leflunomide. Eur. J. Clin. Biomed. Sci. 2026, 12(1), 1-6. doi: 10.11648/j.ejcbs.20261201.11
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Download@article{10.11648/j.ejcbs.20261201.11,
author = {Sobia Shabir and Syeda Tehreem Qamar and Rida Fatima and Ruhanuddin Shaikh and Jawaid Shabir and Shabir Ahmed Shaikh},
title = {Studies of Food & Drug Interaction with Leflunomide},
journal = {European Journal of Clinical and Biomedical Sciences},
volume = {12},
number = {1},
pages = {1-6},
doi = {10.11648/j.ejcbs.20261201.11},
url = {https://doi.org/10.11648/j.ejcbs.20261201.11},
eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.ejcbs.20261201.11},
abstract = {Leflunomide is a well-known rheumatoid arthritis drug. The study's main objective was to evaluate the food and drug interaction studies of leflunomide/visible spectrophotometer technology. A previously developed selective, observant, and exact UV spectroscopic approach for quantitative analysis of leflunomide was applied here. Stock solutions of 1 mMole (0.027 g dissolved in 100ml volumetric flask in methanol) were prepared and diluted to concentration ranges of 0.01 to 0.055 mMole using the same solvent for the leflunomide assay. 50 g mL-1 solutions of leflunomide were prepared to study the potential interaction between leflunomide and fruit juices (apple, orange, and grey fruit). Individually, these solutions were diluted in an equimolar ratio and maintained on a water bath at 37±5°C for three hours. The UV/visible spectrophotometer was being used to evaluate these solutions. Although leflunomide and juices remained constant throughout the experiment, the interaction spectra of all juices with the drug showed that the availability of leflunomide was changed in the presence of all juices. In methanol, leflunomide used to have a maximum absorbance in the ultraviolet region at (259nm), but after interaction with fruit juices (apple, orange, and grey fruit), complex formation was indicated by a change in spectrum shape, pattern, and maximum absorbance with an increase in percentage availability (113.90 -139.64%) as the interaction began, λmax shifted to 271 nm. There was a clear interaction between leflunomide and these juices that could change the drug's pharmacological effects. Leflunomide's maximal absorbance in methanol was found to be 259 nm, its spectra changed following interaction with fruit juices, indicating that a complex was formed. Co-administration of these medications should be avoided, as a result.},
year = {2026}
}
TY - JOUR T1 - Studies of Food & Drug Interaction with Leflunomide AU - Sobia Shabir AU - Syeda Tehreem Qamar AU - Rida Fatima AU - Ruhanuddin Shaikh AU - Jawaid Shabir AU - Shabir Ahmed Shaikh Y1 - 2026/01/30 PY - 2026 N1 - https://doi.org/10.11648/j.ejcbs.20261201.11 DO - 10.11648/j.ejcbs.20261201.11 T2 - European Journal of Clinical and Biomedical Sciences JF - European Journal of Clinical and Biomedical Sciences JO - European Journal of Clinical and Biomedical Sciences SP - 1 EP - 6 PB - Science Publishing Group SN - 2575-5005 UR - https://doi.org/10.11648/j.ejcbs.20261201.11 AB - Leflunomide is a well-known rheumatoid arthritis drug. The study's main objective was to evaluate the food and drug interaction studies of leflunomide/visible spectrophotometer technology. A previously developed selective, observant, and exact UV spectroscopic approach for quantitative analysis of leflunomide was applied here. Stock solutions of 1 mMole (0.027 g dissolved in 100ml volumetric flask in methanol) were prepared and diluted to concentration ranges of 0.01 to 0.055 mMole using the same solvent for the leflunomide assay. 50 g mL-1 solutions of leflunomide were prepared to study the potential interaction between leflunomide and fruit juices (apple, orange, and grey fruit). Individually, these solutions were diluted in an equimolar ratio and maintained on a water bath at 37±5°C for three hours. The UV/visible spectrophotometer was being used to evaluate these solutions. Although leflunomide and juices remained constant throughout the experiment, the interaction spectra of all juices with the drug showed that the availability of leflunomide was changed in the presence of all juices. In methanol, leflunomide used to have a maximum absorbance in the ultraviolet region at (259nm), but after interaction with fruit juices (apple, orange, and grey fruit), complex formation was indicated by a change in spectrum shape, pattern, and maximum absorbance with an increase in percentage availability (113.90 -139.64%) as the interaction began, λmax shifted to 271 nm. There was a clear interaction between leflunomide and these juices that could change the drug's pharmacological effects. Leflunomide's maximal absorbance in methanol was found to be 259 nm, its spectra changed following interaction with fruit juices, indicating that a complex was formed. Co-administration of these medications should be avoided, as a result. VL - 12 IS - 1 ER -
Biomedical Engineering Department, Sir Syed University of Engineering and Technology, Karachi, Pakistan
Biomedical Engineering Department, Sir Syed University of Engineering and Technology, Karachi, Pakistan
Biomedical Engineering Department, Sir Syed University of Engineering and Technology, Karachi, Pakistan
Biomedical Engineering Department, Sir Syed University of Engineering and Technology, Karachi, Pakistan
Computer Engineering Department, Sir Syed University of Engineering and Technology, Karachi, Pakistan
Technology, International Relations Department, Federal Urdu University of Arts, Science & Technology, Karachi, Pakistan
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