*13.8.1. Animal toxicity*

In the acute and sub-acute study of the mixture in Swiss albino mice and Wistar albino rats, respectively, no changes in the behavior and in the sensory nervous system responses were observed. Gastro-intestinal effects were not observed in either male or female mice used in the experiments. The median acute toxicity value (LD50) of the extract was above 20.0 g/kg body weight [86]. There was no significant change observed in the protein levels of the rats treated with lower doses of the extract (50 and 100 mg/kg) compared with control, while an observed significant decrease in the protein levels of the rats treated with a high dose (500 mg/kg) may be a sign of impaired renal function. Also, there was a significant increase (*p* < 0.05) in the plasma creatinine levels of all the treated groups [86]. There was no significant increase in AST and alanine aminotransferase (ALT) in the animals treated with lower doses of the extract compared with control but a significant increase in ALT was observed in the group treated with a high dose of the extract (500 mg/kg). This implies that the extract at the doses used had no effects on the heart tissue but at a high dose could have some deleterious effects on the liver tissue. The extract did neither improve nor produced any deleterious effects on the hematological parameters [86].

used by traditional healers in the treatment of an array of diseases including lumbago, rheu-

Toxicity and Safety Implications of Herbal Medicines Used in Africa

http://dx.doi.org/10.5772/intechopen.72437

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Acute toxicity study of *M. cecropioides* aqueous stem bark extract showed no mortality in rats, at a limit dose of 3000 mg/kg body weight given orally. This is an indication that the extract has low acute toxicity when orally administered. Administration of the aqueous extract for 28 days in a chronic study did not affect most of the biochemical parameters except for creatinine which was significantly elevated. Hematological parameters were not significantly affected during the 28-day treatment. Liver enzymes, AST and ALT, were not affected in the treatment showing that the extract is non-toxic on the hepatocytes. The study concluded that the absence of clinical signs of acute toxicities in human when the extract was orally administered as an antihypertensive may reflect the oral route of administration, low dose administration as well as short duration of exposure when used as an

There is an increasing use of medicinal plants and herbal medicines which contribute significantly to the health of humanity worldwide, especially in developing countries. The limited scientific knowledge among the general population has led to the general assumption that herbal medicines being natural are therefore safe. However, evidence is being adduced from toxicological studies that show plant products to be potentially toxic thus affecting

The source of potential toxicity could be traced to a number of factors: the type of constituents some of which may be intrinsically toxic such as tropane alkaloids and cardiac glycosides though they had been used in traditional medicine. Also, it is noted that the route of administration and dose, of any chemical, are important regarding safety due to chemical or pharmacological interactions; this is undergirded by the need for a regulatory

Serious adverse effects of therapies involving aqueous traditional medicines are rare. However, efforts to investigate toxicity, organ toxicity and cytotoxicity, have involved the use of organic solvent plant extracts and routes of administration which constitute a drawback to

Information on the traditional formulation and use of the herbal medicines should be satisfactory to avoid possible toxicity from the medicinal plants. Manufacturers of herbal medicines should consider standardization of the products while patrons of herbal medicines need to inform their health-care providers about any herbal products they use to ensure effective and safe care. This is to avoid interaction between herbal and allopathic medicines which could

matism, leprosy, chest infections and trypanosomiasis [92].

*13.10.1. Animal toxicity*

antihypertensive agent [93].

**14. Conclusion**

their safe use.

regime for quality.

yield adverse reactions.

the conclusions drawn from such studies.
