Thanks for your question.
The swelling and itching after a mosquito bite is a result of allergic reaction by body induced by mosquito bite.Some people react much more strongly than normal.
You need an anti allergic medication like benadryl and zyrtec to control this.
If anti allergic medicines do not work you may need steroids to decrease the inflammation.Steroids are prescription drug.
Low strength steroid creams can be used for local application at time of holidays as these are available over the counter.1% hydrocortisone cream is available OTC and you can get it from any pharmacy.You may also take benadryl and zyrtec with application of hydrocortisone cream as these are also available OTC.
This is my initial answer.Please reply for any clarification.
You can get these medications prescribed by your doctor and take them with you and use them as needed.
Steroids are not to be used prophylactically that is before the event though you may take zyrtec and benadryl before you reach your destination and continue using them during holiday.
Steroid cream is to be used on any allergic lesion on skin and cannot be used before that.Similarly steroid tablets should be used in case you develop an allergic reaction.
You may also consider using mosquito repellent creams and using nets while sleeping .Try keeping yourself well covered to avoid mosquito bites.
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