How can you combat the feeling of lethargy associated with allergies?

Plenty of rest.: An allergic reaction is a strain on the body. The body is reacting to a substance it regards as foreign and there are many things that happen. These are stressors that use energy in the body, so the best thing, once the reaction is treated, is to get plenty of rest. If you are tsill lethargic, it might be wise to see your doctor to be sure there is no underlying problem, etc..

Allergy: Allergies can make people very tired and so can the use of oral and nasal antihistamines. Treating the allergies is the first step to increased energy but a strong consideration should be for allergy testing and allergy shots for a long term improvement.