My Chiahuahua is an older dog and has slowed down in his exercise and doesn't eat as much. This morning he started throwing up for no reason, he hasn't eaten anything. It's just foamy clear fluid and this seems to be all that is wrong with him. Is there something I can give him to help get him over being sick to his stomach? I don't think it's anything serious and We're both in very bad health so a trip to the Vet will be a last resort. Help us if you can.