Is your dog having an allergic reaction? What is happening? How much does she weigh?
When did it start?
Well, that sounds like a classic allergic reaction - quite likely to bees or wasps especially if it is still cool at night where you are as they are sluggish and easy to catch or step on.
The dose range for Claritin is 0.25 - 0.5 mg/kg. That works out to 7mg to 14mg for a 60lb dog. That works out to giving her ONE of the 10mg tablets.
Please be very sure that it is not Claritin D with pseudoephedrine in it!!
You should see an improvement within 30 minutes. In the meantime, a towel soaked in cold water and wrung out, then placed over her eyes may help to bring the swelling down.
If she is continuing to swell or develops difficulty breathing see an emergency vet immediately!
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