The problem of the supposed toxicity of garlic at certain doses concerns the entire Liliaceae family (onion, shallot, leek, garlic, lily, asparagus, chives, tulip, hyacinth, etc) which have a high quantity of organic sulfur compounds. Thanks to these properties, the plants in question are particularly effective in the treatment of many pathologies in both humans and animals, so much so that they are commonly used in traditional medicine to combat internal parasites above all. From the pharmacognosy it is clear that some Liliaceae, containing active ingredients, require particular attention to the dosages of administration (but this for all plants that contain active ingredients) as, however, and in the same way, attention must be paid to the administration of drugs, scrupulously respecting the dosages and the dosage.These recommendations must also take into account the diversity of the mechanism of action in the different species, that is, attention must be paid to the pharmacokinetics (study of the processes of absorption, distribution, metabolism and excretion of drugs ), to pharmacodynamics (study of the biochemical and physiological effects of drugs and their mechanism of action) and toxicology in different animals, paying particular attention to breed differences in dogs.
Studies:Scientific studies in animals have been available for about 15/20 years since the first in vivo tests were performed (alas..!), on laboratory animals (mainly rats, rabbits and dogs), for scientifically verify the beneficial properties on human health attributed to garlic by popular medicine. In this case, indirect results are available, i.e. they come from tests carried out on laboratory animals, to evaluate the effects on the various organs and systems, trying to understand the principles of pharmacology and toxicology for a more precise evaluation. organic effects on human health. The first direct tests, i.e. carried out by Veterinary Universities or by veterinarians to evaluate the effects of garlic on dogs or cats, have only been available since the 1990s, in particular an Australian study published in the Australian Veterinary Journal , indicates how the bulb can be toxic if ingested in excessive quantities, without specifying the quantities. For greater completeness of information, I recommend delving deeper into the topic by consulting Laura Murphy's article Pets By Nature where other studies relating to onion and garlic are reported. In the same year at the Hokkaido Univ. an important study on the effects of garlic in dogs and humans was published (Acceleration of superoxide generation in polymorphonuclear leukocytes and inhibition of platelet aggregation by alk(en)yl thiosulfates derived from onion and garlic in dogs and humans *H. S. Chang, O. Yamato, , Y. Sakai, M. Yamasaki and Y. Maede Laboratory of Internal Medicine, Department of Veterinary Clinical Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo 060-0818, Japan 27 May 2003; ) The same authors followed in 2004 with another study on platelet aggregation and the role of garlic, this time only in dogs. Indicted molecule:N-propyl disulfide causes hemolytic anemia which manifests itself with vomiting and diarrhea. Heinz bodies are formed in the erythrocytes, resulting in weakness and rupture of the cell membrane. There are other molecules, however, that are considered toxic, including: S-methylcysteine sulfoxide, methyl disulfide, allyl disulfide. We must underline that these compounds are present especially in onions and the content in garlic is relative.
In conclusion, however, garlic represents one of the oldest medicinal plants and one of the most widespread condiments in the world with which dogs and cats have always come into contact. Together with other lily plants, in addition to its parasite control properties, this bulbous plant is able to stabilize the DNA of healthy cells and carry out a very effective preventive action against various types of cancer of the gastrointestinal tract both of the prostate.