Background: Lannea microcarpa Engl. and K. Krause (Family Anacardiaceae), a tropical tree is used traditionally used in Africa for both medicinal and non-medicinal purposes. Folkoric uses of the plant include wound healing, conjunctivitis, stomatitis and gingivitis among others. Inflammatory reactions are involved in several diseases which this plant is traditionally used to manage. This study was therefore aimed at investigating the antiinflammatory effects of the aqueous extract of Lannea microcapa.Methods: Oedema was induced in the right hind paws of Sprague Dawley rats (200-250g, 12 weeks old, n=5) using dextran sulphate solution whiles ear oedema was induced in ICR mice (25-30g, 6 weeks old, n=5) using xylene solutions. Aqueous extracts of ALM (30, 100 and 300mg kg-1) were administered in a set of rats and mice for both prophylactic and therapeutic studies. In the dextran sulphate-induced paw oedema, rats (200-250g) were treated orally with ALM (30, 100 and 300 mg kg-1) for both prophylactic and therapeutic studies. The paw thickness of the rats was measured before and after dextran sulphate injection at an hourly interval for 5 h. For xylene-induced ear oedema, ICR mice (25-30g) were given the same doses of the ALM and the ear weight of mice were measured after 2 h.Results: In the dextran sulphate-induced paw oedema, the ALM reduced the mean maximal paw oedema significantly (P ≤0.05) to 36.392±9.207% and 26.050±3.396% at 100 and 300 mg kg-1 (prophylaxis) and 32.192±5.670%, 31.398±6.921% and 31.593±5.841% at 30, 100 and 300 mg kg-1 (therapeutic) in dose dependent manner when compared to the control respectively. Similarly, the ALM dose dependently showed a significant (P ≤0.05) reduction of percentage mean oedema in xylene-induced ear oedema by 43.56%, 59.63% and 68.07% at 30, 100 and 300 mg kg-1 when compared to the control respectively.Conclusions: Aqueous extract of Lannea microcapa (30 -300 mg kg-1) caused significant reduction of oedema in both dextran sulphate-induced paw oedema and xylene-induced ear oedema
