Do not use if you are pregnant or breastfeeding. Consult a health care practitioner prior to use if you are taking antineoplastic (anticancer) agents, anticoagulants or immunosuppressants, or if you have a clotting disorder or an autoimmune disease. Consult a health care practitioner if symptoms persist or worsen. Pau d’Arco may elicit an allergic reaction in those individuals sensitive to wood dust.