I can't tolerate most meds, so I have experimented with alternative meds. I get fabulous, and almost instant, relief from allergy symptoms with a homeopathic remedy, with no side effects. About 4 out of 5 people respond positively to homeopathy, and the rest simply don't respond. The only likely reaction is in those allergic to milk, because the pellets are made with a milk-sugar base.
Many doctors object to homeopathy, and some will argue that some remedies are based upon poisonous plants. True, but there may be one molecule, if even that, in the actual remedy. (many modern medicines are also made from highly toxic natural substances.) The process of making the remedies titrates the original substance away, but leaves behind only an energy signature that the body can still recognize and respond to. I have yet to see a scientific explanation of how this can be, but modern molecular science is getting closer.
I've known quite a few children who respond very well to this approach for all sorts of physical and emotional problems. It is very popular in Europe. The over-the-counter remedies are safe and have no side effects. (Or if they do, the websites will make you aware of what those effects might be. They are usually called "mentals" because they are usually mood changes.)
The one I use is called Histaminum hydrochloricum, but there are a few others that can be safely used with children. The trick, and this may take a little experimentation, is to find the one that is best matched to the particular person's symptoms.
Google "homeopathy for children" to get quite a few sites that can guide you through the process.