If you are really allergic to cats then it might be challenging to live with one. Best anti allergic of mild doses is Allegra 120 for daily use. You can use almost for a month without worrying about any side effects.
However if after a month you still feelnits not working up then there are injection shots available which can give you a long term immunity based on your body physiology. 10 years to life-long
Next Steps
start anti allergic medication.
Health Tips
wash hands every time you touch the cat