Garlic, adverse reaction

Adverse reactions may include acneiform eruptions allergic dermatitis arthropathy multiple cases of cholestatic and fulminant hepatitis drowsiness fatigue headache hepatotoxicity resembling viral or alcoholic hepatitis impotence metallic or garlic-like aftertaste peripheral neuropathy polyneuritis optic or retrobulbar neuritis restlessness occasional skin eruptions. 

Other spices, too, for example, mustard, paprika, flour additives, and garlic (Dannaker and White 1987, Scholl and Jensen-Jarolim 2004) as well as many food products, such as milk proteins (casein), whey proteins (a-lactalbumin, P-lactoglobulin), and wheat proteins, which are not always obvious food ingredients (hidden ingredients) (Lopata and Potter 2000, Chapters 6 and 13), may cause adverse reactions. 

The recommended dose is about 4g of fresh garlic daily, which is equivalent to approximately 8 mg garlic oil or 600 to 900 mg garlic powder preparations standardized to 1.3% alliin content. Adverse effects of garlic are usually mild and transient they include breath and body odor, allergic reactions, nausea, heartburn, and flatulence. 

Acetylene (Figure 13.1) is widely used as a chemical raw material and fuel for oxyacetylene torches. It was once the principal raw material for the manufacture of vinyl chloride (see reaction 13.2.4), but other synthetic routes are now used. Acetylene is a colorless gas with an odor resembling garlic. Though not notably toxic, it acts as an asphyxiant and narcotic and has been used for anesthesia. Exposure can cause headache, dizziness, and gastric disturbances. Some adverse effects from exposure to acetylene may be due to the presence of impurities in the commercial product. 

While exaggerated intakes such as those in China may occur without adverse consequences, not all individuals would be expected to consume large quantities of garlic without complications. A spectrum of adverse allergic reactions, albeit of low incidence. 

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