Traditional methods of repelling and/or killing bed bugs include the use of plants, fungi, and insects (or their extracts), such as black pepper; black cohosh (Actaea racemosa); Pseudarthria hookeri; Laggera alata (Chinese yángmáo cǎo | 羊毛草); Eucalyptus saligna oil; henna (Lawsonia inermis or camphire); "infused oil of Melolontha vulgaris" (presumably cockchafer); fly agaric (Amanita muscaria); tobacco; "heated oil of Terebinthina" (i.e. true turpentine); wild mint (Mentha arvensis); narrow-leaved pepperwort (Lepidium ruderale); Myrica spp. (e.g. bayberry); Robert geranium (Geranium robertianum); bugbane (Cimicifuga spp.); "herb and seeds of Cannabis"; "opulus" berries (possibly maple or European cranberrybush); masked hunter bugs (Reduvius personatus), "and many others".
You can develop a skin infection if you scratch the bites. Rarely, a more severe allergic reaction to the bites could produce larger welts, blisters, or anaphylaxis. Bedbugs may also trigger asthma attacks and getting too many repeated bites could lead to anemia. Anxiety, insomnia, and sleep disturbances are common due to the stress of discovering bedbugs.
One bed bug will usually take more than one bite. Once a bed bug inserts its mouthparts and finds a suitable blood vessel, it will begin feeding. However, finding the right blood vessel may take more than one injection into the skin. In addition, bed bugs are very sensitive to movement by the host they are feeding on. Therefore, if a sleeping person moves, a feeding bed bug will probably withdraw its mouthparts and begin its search for a blood meal on another part of the body. It’s important to remember that the number of bites a person receives is not indicative of the number of bed bugs that feed on that person.