K.A.
After looking at my medication allergies(there are many!) and taking into considering I was breastfeeding at the time my doctor poored through her book. In the end she gave me a prescription for Zyrtec, which thankfully you can now get over the counter, in generic now even. I have a pretty good range of allergies and allergy triggered asthma and this has worked well for me and I breastfed my son for years. I only take it when I need it which is my suggestion to you. You're not going to be there a very long time so it should be fine.
Best of luck!