This review from 2013 examines the pharmacological effects of A. sativum, A. hirtifolium, and their active constituents. Garlic extracts were examined for antimicrobial, cardiovascular, lipid and immune effects.
Concluding a high tolerance and low risk for consumption of garlic extracts particularly with standardized allicin content.
References:
Mikaili P, Maadirad S, Moloudizargari M, Aghajanshakeri S, Sarahroodi S. Therapeutic uses and pharmacological properties of garlic, shallot, and their biologically active compounds. Iran J Basic Med Sci. 2013 Oct;16(10):1031-48. PMID: 24379960; PMCID: PMC3874089.