Coughing is a common reflex that helps clear irritants from the airways. While typically a protective mechanism, a forceful or prolonged cough can sometimes lead to an uncomfortable side effect: vomiting. This phenomenon involves interconnected bodily responses and can be triggered by various underlying conditions. Understanding these connections can demystify why a cough might result in throwing up.
The Body’s Response
The cough reflex is a natural defense mechanism designed to expel foreign particles and excess mucus from the respiratory tract. It involves a coordinated series of actions: a deep inhalation, closure of the vocal cords, and then a forceful exhalation against the closed airway, followed by rapid opening of the vocal cords to release air. This forceful expulsion of air helps to clear the airways.
The gag reflex is another protective mechanism, preventing foreign objects from entering the throat and airways. It is triggered by stimulation of the back of the throat, soft palate, or tongue, leading to a reflexive contraction of pharyngeal muscles. Both the cough and gag reflexes share neural pathways in the brainstem, a lower part of the brain responsible for many involuntary functions. Due to this close neurological connection, an intense cough can inadvertently stimulate the gag reflex, leading to retching or vomiting.
Forceful coughing significantly increases intra-abdominal pressure. During a strong cough, the diaphragm and abdominal muscles contract, compressing the abdominal cavity. This rise in pressure can squeeze the stomach, contributing to the expulsion of its contents and inducing vomiting. The combined effect of gag reflex stimulation and increased abdominal pressure explains the physiological link between severe coughing and vomiting.
Underlying Causes
Various conditions can cause coughing severe enough to induce vomiting. Acute respiratory infections are common culprits, including severe colds, influenza, bronchitis, and pneumonia. These infections often lead to inflammation and increased mucus production, resulting in intense coughing fits that can trigger the gag reflex or lead to vomiting. Whooping cough, or pertussis, is particularly known for causing violent, uncontrollable coughing attacks often followed by gagging or vomiting, especially in children.
Allergies and post-nasal drip can also provoke this reaction. When allergens or irritants cause excess mucus production, this mucus can drip down the back of the throat. This post-nasal drip irritates the airways, stimulating coughing, and the swallowed mucus can also cause nausea or trigger the gag reflex, leading to vomiting.
Asthma, a chronic inflammatory condition of the airways, can involve coughing so forceful it induces vomiting, particularly during severe attacks. Gastroesophageal Reflux Disease (GERD) is another common cause, where stomach acid flows back into the esophagus and sometimes into the airways. This acid irritation can trigger a chronic cough, which may then lead to vomiting.
Exposure to environmental irritants, such as smoke, strong fumes, or pollutants, can also provoke severe coughing that results in vomiting. These irritants can inflame the respiratory passages, leading to a heightened cough response. The body’s attempt to clear these irritants through forceful coughing can inadvertently lead to the expulsion of stomach contents.
When to Consult a Doctor
While coughing that leads to vomiting is not always a sign of a serious condition, certain symptoms warrant medical attention. Seek immediate medical care if you or someone you are caring for vomits blood or material that looks like coffee grounds. This can indicate internal bleeding and is a serious concern.
It is important to consult a doctor if you experience:
- Signs of severe dehydration, such as decreased urination, dry mouth, excessive thirst, or lethargy.
- High fever, severe chest pain, or difficulty breathing accompanying the cough and vomiting.
- Coughing and vomiting lasting more than a few days to a week, or if symptoms worsen.
- Significant unexplained weight loss alongside these symptoms.
For infants and very young children, any persistent coughing and vomiting should prompt a doctor’s visit, as they are more susceptible to dehydration and complications.