Assessment of KaraShieldTM properties in supporting the immune health of healthy subjects: a randomized, parallel, double-blind, placebo-controlled clinical study


  • Frank Lichtenberger Piedmont Healthcare, Statesville, NC, USA
  • Krishna Rajendran Karallief Inc, Boston, MA, USA
  • Keri Layton Whole Family Wellness, Winchester, MA, USA
  • Sucharitha Lakshminarayan Shetty's Hospital, Bengaluru, Karnataka, India
  • Latha Krishnamurthy Sri Venkateshwara Hospital, Bengaluru, Karnataka, India
  • Dheeraj K. Deep D2L Clinical Solutions, Bengaluru, Karnataka, India



Clinical trials, Upper respiratory tract infections, Immunostimulation, KaraShieldTM, Indian herb


Background: This study aims to investigate whether a novel herbal extract blend, KaraShieldTM could be used to help build a healthy immune system that could reduce the number of incidences or severity of common upper respiratory tract infections (URTIs).

Methods: A randomized, parallel, double-blind, placebo-controlled clinical study of 60 days was done on 120 healthy subjects allocated to a treatment arm (500 mg/day, KaraShieldTM) or placebo arm (500 mg/day).

Results: A 500 mg daily dosage of KaraShieldTM significantly improved the subjects' immune health as measured by parameters such as the frequency and severity of upper respiratory tract conditions, the serum IgG level, mean ISQ raw score, WURSS scale score, CRP level in the serum and WHOQOL-BREF score at the end of the study period of sixty days from the baseline compared to that of the placebo. The investigated product was found to be safe and well tolerated by the subjects.

Conclusions: KaraShieldTM may represent a promising safe and effective formulation for building a healthy immune system that could then counteract URTIs.


Zhang H, Miao J, Su M, Liu BY, Liu Z. Effect of fermented milk on upper respiratory tract infection in adults who lived in the haze area of Northern China: A randomized clinical trial. Pharm Biol. 2021;59:645-50.

Somerville VS, Braakhuis AJ, Hopkins WG. Effect of flavonoids on upper respiratory tract infections and immune function: a systematic review and meta-analysis. Adv Nutr. 2016;7:488-97.

Heinz SA, Henson DA, Austin MD, Jin F, Nieman DC. Quercetin supplementation and upper respiratory tract infection: A randomized community clinical trial. Pharmacol Res. 2010;62:237-42.

Jain N, Lodha R, Kabra S. Upper respiratory tract infections. Indian J Pediatr. 2001;68:1135-8.

Lunn AD. Reducing inappropriate antibiotic prescribing in upper respiratory tract infection in a primary care setting in Kolkata, India. BMJ Open Qual. 2018;7:e000217.

Khan MY, Aliabbas S, Kumar V, Rajkumar S. Recent advances in medicinal plant biotechnology. Indian J Biotechnol. 2009;8(1).

Pan S-Y, Litscher G, Chan K, Yu Z-L, Chen H-Q, Ko K-M. Traditional medicines in the world: where to go next?: Hindawi. 2014;739895.

Ponticelli M, Bellone ML, Parisi V, Iannuzzi A, Braca A, de Tommasi N, et al. Specialized metabolites from plants as a source of new multi-target antiviral drugs: a systematic review. Phytochem Rev. 2023;1-79.

Adiguna SBP, Panggabean JA, Atikana A, Untari F, Izzati F, Bayu A, et al. Antiviral activities of andrographolide and its derivatives: mechanism of action and delivery system. Pharmaceuticals. 2021;14:1102.

Tharakan A, Shukla H, Benny IR, Tharakan M, George L, Koshy S. Immunomodulatory effect of Withania somnifera (Ashwagandha) extract—a randomized, double-blind, placebo controlled trial with an open label extension on healthy participants. J Clin Med. 2021;10:3644.

Logambal S, Venkatalakshmi S, Dinakaran Michael R. Immunostimulatory effect of leaf extract of Ocimum sanctum Linn. in Oreochromis mossambicus (Peters). Hydrobiologia. 2000;430:113-20.

Vahedi S. World Health Organization Quality-of-Life Scale (WHOQOL-BREF): analyses of their item response theory properties based on the graded responses model. Iran J Psychiatry. 2010;5:140.

Saeidnia S, R Gohari A, Manayi A. Reverse pharmacognosy and reverse pharmacology; two closely related approaches for drug discovery development. Curr Pharm Biotechnol. 2016;17:1016-22.

Wen C-C, Chen H-M, Yang N-S. Developing phytocompounds from medicinal plants as immunomodulators. Adv Bot.Res. 2012;62:197-272.

Melbye H, Hvidsten D, Holm A, Nordbø SA, Brox J. The course of C-reactive protein response in untreated upper respiratory tract infection. Br J Gen Pract. 2004;54:653-8.

Xiong Y, Rajoka MSR, Mehwish HM, Zhang M, Liang N, Li C, et al. Virucidal activity of Moringa A from Moringa oleifera seeds against Influenza A Viruses by regulating TFEB. Int Immunopharmacol. 2021;95:107561.

Chen J-X, Xue H-J, Ye W-C, Fang B-H, Liu Y-H, Yuan S-H, et al. Activity of andrographolide and its derivatives against influenza virus in vivo and in vitro. Biol Pharm Bull. 2009;32:1385-91.

Caceres D, Hancke J, Burgos R, Sandberg F, Wikman G. Use of visual analogue scale measurements (VAS) to asses the effectiveness of standardized Andrographis paniculata extract SHA-10 in reducing the symptoms of common cold. A randomized double blind-placebo study. Phytomedicine. 1999;6:217-23.

Mueller SN, Rouse BT. Immune responses to viruses. Clin Immunol. 2008;421.

Chow MY, Pan HW, Seow HC, Lam JK. Inhalable neutralizing antibodies–promising approach to combating respiratory viral infections. Trends Pharmacol Sci. 2023;44(2):85-97.

Mondal S, Varma S, Bamola VD, Naik SN, Mirdha BR, Padhi MM, Mehta N, et al. Double-blinded randomized controlled trial for immunomodulatory effects of Tulsi (Ocimum sanctum Linn.) leaf extract on healthy volunteers. J Ethnopharmacol. 2011;136:452-6.




How to Cite

Lichtenberger, F., Rajendran, K., Layton, K., Lakshminarayan, S., Krishnamurthy, L., & Deep, D. K. (2023). Assessment of KaraShieldTM properties in supporting the immune health of healthy subjects: a randomized, parallel, double-blind, placebo-controlled clinical study. International Journal of Basic & Clinical Pharmacology, 13(1), 1–12.



Original Research Articles