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Watch out for the smokers' cough. Watch for yellowing teeth. Look for yellow stains on your child's fingers. Pay attention if your teen is wheezing. Notice any shortness of breath. Look for a higher frequency of respiratory diseases.

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One of the most common and immediate symptoms of smoking is the persistent smokers' cough. It can appear in as little as a few days after beginning smoking and can even be present with casual (not heavy) smoking. The cough is usually the worst in the morning and lessens throughout the day. It is usually accompanied by phlegm which can be clear, yellow, or even green. Smoking causes teeth to turn yellow over time, so be mindful of this if your child's teeth start to look more yellow. Also take notice if your child suddenly becomes interested in teeth whitening products like special whitening toothpaste or whitening strips. While yellowing teeth may take some time to appear, smoking cigarettes can cause yellow stains on your teen's fingers and fingernails almost immediately. A wheezing sound can indicate several different physical conditions in your child, but one of them is damaged airways/lungs from smoking. Shortness of breath is a tell-tale sign of a smoker. If your child is suddenly not able to be active for long periods of time or takes longer to catch their breath after physical activity, you should consider the possibility that they might be smoking. Smokers are more prone to getting certain respiratory diseases like colds, bronchitis, and pneumonia. If your child is suddenly getting sick more frequently with diseases like this, you might need to be concerned that these illnesses are the side effects of a new smoking habit.