What makes you think that she is sick? Fever, stuffed up nose, etc? If baby has a cold there isn't much you can do. There isn't much you can do for an adult with a cold except rest, humidifier, fluids and monitor for fever. When Jack had a cold he was spitting up more (not throwing up, I feel like there is a difference. Throwing up is forceful, spit up happens with burps or hiccups and is a pretty mellow occasion) but this was because the post-nasal drip was filling his tummy so he couldn't eat his normal amount of milk.
She's had a cold for about a week so we've been taking her into the bathroom with us in the morning to sit in her bouncer in the steam, using the snot sucker and saline on occassion. She had a a slight fever a few days ago but I figured it was teething it , she has a tooth that's slowly breaking through. It's definitely the forceful throwing up about 20 minutes after she eats. She has been eating less ( 4oz per bottle instead of the usual 6-7oz). I'm not super worried at this point, just cautious.