N. SIDE EFFECT
SIDE EFFECT
Symptoms such as severe itching and redness, local allergic reactions (urticaria), anaphylaxis, irritant contact dermatitis, follicular pseudolymphoma and mucosal synechiae have been reported very rarely, especially when humans are repeatedly exposed to leeches for medicinal purposes.
In severe cases of generalized itching, topical corticosteroids and oral antihistamines should be prescribed. Signs of regional lymphadenitis, slight swelling, and pain of regional lymph nodes on the side of leech application and sub febrile temperature can occur in 6.4–13.4% of the treated patients and usually appears after 3-4 leech applications. In very rare cases, allergic skin reactions have been observed [35].
The patients may lose 5–15 mL of blood per leech, per session. However, the wound may continue to ooze up to 24 hours after the leech is removed. Accordingly, hematologic evaluations should be performed every 4 hrs. and consist of complete blood cell count, partial thromboplastin time, and serum chemistry studies. However, the number of hematocrit checks depends on the number of leeches used, frequency of sessions, and total duration of therapy. In many cases, the patients have to receive blood transfusions when the hemoglobin level is lower than 8 g/dL [6,16,18]. If the continuation of bleeding is required, the bite areas could be cleaned hourly with gauze soaked in isotonic sodium chloride solution or heparin solution (5,000 U/mL) to stimulate hemorrhage from the bite sites [35].
The excess bleeding can be however of concern, and transfusions may be needed. Special care should be taken in patients with a tendency to hemorrhage, severe anemia or for those taking anticoagulants or platelet-inhibitor drugs.
It is recommended to monitor the blood pressure of the patient before and after leeching.
The symbiotic Aeromonas bacteria of the medicinal leeches may cause sepsis and secondary infections in 4-20% [48] of the cases if the leeches were applied to or close to open wounds, e.g., in reconstructive surgery or in immunosuppressed patients. Such patients should receive prophylactic treatment with antibiotics [35]. (See also Prophylaxis)
When applied on intact skin however, e.g., in patients treated for osteoarthritis, local pain, arterial hypertension, and different forms of spondylosis and dorsopathies, Aeromonas infections are extremely rare.
Regarding the psychological aspects, many patients treated with leeches and who had successful treatment changed their attitude towards hirudotherapy in a positive way. Nevertheless, it might be necessary to prepare the patients psychologically before the application of leeches [49].