Antiviral garlic

Garlic is one of the most common botanical remedies used by patients with human immunodeficiency virus (HIV), probably because of to the antiviral claim associated with its consumption, as well as the possibility of lowering total serum cholesterol, which could counteract the common side effect of hypercholesterolemia associated with the use of antiretroviral drug regimens. 

Because of reported antiplatelet effects, patients using anticlotting medications (eg, warfarin, aspirin, ibuprofen) should use garlic cautiously. Additional monitoring of blood pressure and signs and symptoms of bleeding is warranted. Garlic may reduce the bioavailability of saquinavir, an antiviral protease inhibitor, but it does not appear to affect the bioavailability of ritonavir. 

Garlic is known to possess diaphoretic, expectorant, antispasmodic, antiseptic, bacteriostatic, antiviral, hypotensive, and anthelmintic properties, and to promote leucocytosis. Traditionally, it has been used to treat chronic bronchitis, respiratory catarrh, recurrent colds, whooping cough, bronchitic asthma, and influenza. 

Garlic extracts have been shown to inhibit the growth of a variety of bacteria and fungi. In addition, garlic extracts have been shown to have antiviral properties. Onion extracts have also been shown to have antibacterial properties. 

Garlic has been shown in in vitro studies to have antiviral activity against several viruses including cytomegalovirus, influenza B, Herpes simplex virus types 1 and 2, parainfluenza virus type 3, and human rhino virus type 2(40). Antiviral activity is thought to be caused more by the ajoene component than the allicin component of garlic (46). 

Some of the most powerful traditional blends of spices are chili powder (capsicums, onion, paprika, garlic, cumin, oregano), five-spice powder (white or black pepper, cinnamon, anise, fennel, cloves), salsa (capsicums, onion, garlic, tomatoes, lime), and curry powder (tumeric [a potent antibacterial antifungal, antiparasitic, and antiviral herb], curry leaves [a potent antiamebic, antimalarial, and antidiarrheal herb], cumin, cardamom, ginger, mustard, coriander). 

Although information is limited, a reduction in saquinavir plasma levels of the magnitude seen in the first study could diminish its antiviral efficacy. All garlic supplements should probably be avoided in those taking saquinavir as the sole protease inhibitor (no longer generally recommended). While the pharmacokinetic effect on single-dose ritonavir was not clinically important, this requires confirmation in a multiple-dose study. 

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