When you need to improve your immune system to counter an infection like histoplasmosis, many people turn to the time-honored remedy of neem leaves. Popularized in Ayurvedic medicine, but rapidly spreading in popularity around the world, neem leaves are known to boost your immunity and detoxify the body. This is bad news for the fungal infection in your respiratory tract, making neem a great remedy for histoplasmosis. Neem leaves can be brewed and steeped into a flavorful tea and drunk regularly, either as a preventative measure or a treatment.