Preclinical Safety Evaluation of Allicin on Topical Application
Further evaluation of skin irritability and irritation induced by
allicin was performed to assess the suitability and safety of allicin
for topical applications. Skin changes were observed after allicin
treatment daily, including erythema and edema. As shown in Figures 2A
and 2B, no allergic reactions were observed in the allicin
administration group. After four months of continuous application,
compared with the blank solvent control group, allicin led to slight
skin irritation in the first three months and yielded no irritation in
the fourth month due to gradual development of skin tolerance (figure
2C). Next, we inspected the toxicity of allicin for long-term
application, and there was no
significant influence on weight (Figure 2D). The organ index was
calculated after the major organs were resected and weighed, using the
formula Organ index = organ weight (mg) /
body weight (kg) ×100%. The
heart, liver, spleen, and thymus indexes showed that allicin yielded no
significant difference in body weight and major organs compared with the
control group (Figure 2E). Hematology (Figure 2F, Table S2) and
biochemistry (Table S3) indicators were analyzed before and after
continuous topical application of allicin, with no significant changes.
Our data demonstrated that allicin was safe and well-tolerated for
long-term external use.