Thanks for asking the query,
Swelling in the tongue can be due to several reasons few are;
Oral infections, nutritional deficiencies, neurofibromatosis, oral cancers due to use of tobacco, betel nut chewing, long standing trauma, intake of hot and spicy foodstuffs.
I would suggest you to visit to an Oral and Maxillofacial Surgeon for clinical examination and evaluation which helps in exact diagnosis and treatment.
occurs due to fever
, prolonged use of medications, salivary gland
Meanwhile you maintain a good oral hygiene
, use antiseptic mouthwash gargles tiwce daily.
Take antioxidant suplements.
Drink plenty of water and keep yourself hydrated.
Hope this helps out.