Antihistamine

"Yes. Doctor McKay uses them frequently, along with antihistamines, antacids, motion sickness pills ..."

- Teyla Emmagan

Antihistamines are used as treatment for symptoms of allergies such as runny nose. Daniel Jackson and Janet Fraiser both took them to deal with allergies and they were also used to starve the body of histamine to fight off the virus that was brought back from the Land of Dark. Dr. Rodney McKay is known to take them, although it is hinted that they are unnessecary.