Hello ,
Thanks for posting your query.
Lethargy and dizziness could be due to conditions like dehydration, hypotensive(decreased blood pressure) or hypoglycemia(decreased sugar) or any infection.
If she is feeling cold or shivering there is more likely an infectious cause.
However in order to help you with better guidance I would like to know further details which are lacking in your present query.
1.The exact onset(whether sudden or gradual etc), duration and progress of her symptoms.
2. The associated symptoms if any like fever, vomiting, nausea, decreased intake, decreased urination, headache etc.
3.Any past medical history or significant family history of any illness.
4.Any change in routine or travel etc.
5.Whether taken any medications or shown to gp, or any tests done.
Hope you can get back to me as soon as feasible, so that I can guide you appropriately.
Awaiting your response.
Regards,

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Hello,
Thanks for the follow up.
Sudden appearance of such symptoms after exposure to other kids indicates most probably a viral infection she has caught on from there.Sometimes viral infections begin with such prodromal symptoms before any other full blown symptoms like rash or diarrhoea or fever occur.
The diagnosis can be confirmed only after a thorough physical examination of your daughter by her pediatrician and if needed he might start apropriate antiinflammatory medications.
Though most viral infections are self resolving within a couple of weeks, some might need supportive treatment.He might order few blood tests like blood sugar, electrolytes, complete blood counts, liver profile etc for confirmation of diagnosis and prevention of complications.

Alternatively, you may wait and watch for the progression of symptoms and meanwhile do the following for symptomatic relief.

1.Ensure she has plenty of water or sips of oral rehydration solution (WHO recommended ORS)throughout the day to maintain her hydration.This may decrease her lethargy and dizziness.
2.To increase her apetite you may give her natural probiotics and if problem persists then apetite stimulants (as per doctors prescription.
3.Avoid any strenous physical activity and let her take plenty of rest and sleep.
4.A multivitamin supplement might be started if only lethargy persists.
Remember to watch out for any danger signs like, bleeding from any site, blood in stools, decreased urination, bursting headaches, neck rigidity, fast breathing etc.If any of these develop please seek prompt medical consultation.
As of now the situation does not seem much worrisome.
Hope that answers your query.
Wishing your child a speedy recovery and good health.
Regards

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