Medical Precautions Note: If you suffer from heartburn, kidney or gall bladder problems or have a citrus allergy consult your doctor before using these remedies or drinking lemon juice. To protect your teeth enamel, wait at least half an hour before brushing your teeth after chewing, drinking or rinsing with lemon juice. Rubbing lemon juice or oil and drinking lemon juice is not suitable for children under the age of 10. Lemons are effective home remedies for a variety of health concerns but in the case of serious illness always consult your doctor first.