Some of the herbs herbalists routinely use for these sorts of conditions, are in fact relatively common British wild plants. Herbs such as ribwort or plantain (Plantago lanceolata) (actually a very common wild plant ) Elderflower (Sambuccus niger) (again, soon to be taking a starring role with its masses of white flowers in our hedgerows) and eyebright (Euphrasia officinalis) - a tiny semi-parasitic plant with a white flower that under the very ancient system of medicine known as the 'doctrine of signatures' was used to treat eye complaints because of its eye-like appearance - not really that obvious, but it is a small white flower that almost winks at you from the grassy well-drained places in which it commonly grows. In fact modern herbal medicine still acknowledges this use today (although not all 'doctrine of signatures' uses have passed into modern practice) and it is still a very useful herb in the armory of the professional herbalist for some eye problems and upper respiratory tract complaints.
This advice is only meant for educational purposes and should not be used as a basis for self-treatment. Remember that herbs can interact with other drugs and may be contra-indicated if you have certain medical conditions, are pregnant or lactating. Take care when using wild plants or herbs, that you have the correct species from a reliable source. Best consult a medical herbalist.