Nasal congestion in the context of "Cluster headache"

The symptoms of COVID-19 are variable depending on the type of variant contracted, ranging from mild symptoms to a potentially fatal illness. Common symptoms include coughing, fever, loss of smell and taste, with less common ones including headaches, nasal congestion and runny nose, muscle pain, sore throat, diarrhea, eye irritation, and toes swelling or turning purple, and in moderate to severe cases, breathing difficulties. People with the COVID-19 infection may have different symptoms, and their symptoms may change over time.

Three common clusters of symptoms have been identified: a respiratory symptom cluster with cough, sputum, shortness of breath, and fever; a musculoskeletal symptom cluster with muscle and joint pain, headache, and fatigue; and a cluster of digestive symptoms with abdominal pain, vomiting, and diarrhea. In people without prior ear, nose, or throat disorders, loss of taste combined with loss of smell is associated with COVID-19 and is reported in as many as 88% of symptomatic cases.

Nasal sprays are used to deliver medications locally in the nasal cavities or systemically. They are used locally for conditions such as nasal congestion and allergic rhinitis. In some situations, the nasal delivery route is preferred for systemic therapy because it provides an agreeable alternative to injection or pills. Substances can be assimilated extremely quickly and directly through the nose. Many pharmaceutical drugs exist as nasal sprays for systemic administration (e.g. sedative-analgesics, treatments for migraine, osteoporosis and nausea). Other applications include hormone replacement therapy, treatment of Alzheimer's disease and Parkinson's disease. Nasal sprays are seen as a more efficient way of transporting drugs with potential use in crossing the blood–brain barrier.

Sinusitis, also known as rhinosinusitis and commonly known as a sinus infection, is an inflammation of the mucous membranes that line the sinuses resulting in symptoms that may include production of thick nasal mucus, nasal congestion, facial congestion, facial pain, facial pressure, loss of smell, or fever.

Sinusitis is a condition that affects both children and adults. It is caused by a combination of environmental factors and a person's health factors. It can occur in individuals with allergies, exposure to environmental irritants, structural abnormalities of the nasal cavity and sinuses and poor immune function. Most cases are caused by a viral infection. Recurrent episodes are more likely in people with asthma, cystic fibrosis, and immunodeficiency.

Rhinitis, also known as coryza, is irritation and inflammation of the mucous membrane inside the nose. Common symptoms are a stuffy nose, runny nose, sneezing, and post-nasal drip.

The inflammation is caused by viruses, bacteria, irritants or allergens. The most common kind of rhinitis is allergic rhinitis, which is usually triggered by airborne allergens such as pollen and dander. Allergic rhinitis may cause additional symptoms, such as sneezing and nasal itching, coughing, headache, fatigue, malaise, and cognitive impairment. The allergens may also affect the eyes, causing watery, reddened, or itchy eyes and puffiness around the eyes. The inflammation results in the generation of large amounts of mucus, commonly producing a runny nose, as well as a stuffy nose and post-nasal drip. In the case of allergic rhinitis, the inflammation is caused by the degranulation of mast cells in the nose. When mast cells degranulate, they release histamine and other chemicals, starting an inflammatory process that can cause symptoms outside the nose, such as fatigue and malaise. In the case of infectious rhinitis, it may occasionally lead to pneumonia, either viral or bacterial. Sneezing also occurs in infectious rhinitis to expel bacteria and viruses from the respiratory tract.

Pseudoephedrine, sold under the brand name Sudafed among others, is a sympathomimetic medication which is used as a decongestant to treat nasal congestion. It has also been used off-label for certain other indications, like treatment of low blood pressure. At higher doses, it may produce various additional effects including stimulant, appetite suppressant, and performance-enhancing effects. In relation to this, non-medical use of pseudoephedrine has been encountered. The medication is taken by mouth.

Side effects of pseudoephedrine include insomnia, elevated heart rate, increased blood pressure, restlessness, dizziness, anxiety, and dry mouth, among others. Rarely, pseudoephedrine has been associated with serious cardiovascular complications like heart attack and hemorrhagic stroke. Some people may be more sensitive to its cardiovascular effects. Pseudoephedrine acts as a norepinephrine releasing agent, thereby indirectly activating adrenergic receptors. As such, it is an indirectly acting sympathomimetic. Pseudoephedrine significantly crosses into the brain, but has some peripheral selectivity due to its hydrophilicity. Chemically, pseudoephedrine is a substituted amphetamine and is closely related to ephedrine, phenylpropanolamine, and amphetamine. It is the (1S,2S)-enantiomer of β-hydroxy-N-methylamphetamine.

Ephedrine is a central nervous system (CNS) stimulant and sympathomimetic agent that is often used to prevent low blood pressure during anesthesia. It has also been used for asthma, narcolepsy, and obesity but is not the preferred treatment. It is of unclear benefit in nasal congestion. It can be taken by mouth or by injection into a muscle, vein, or just under the skin. Onset with intravenous use is fast, while injection into a muscle can take 20 minutes, and by mouth can take an hour for effect. When given by injection, it lasts about an hour, and when taken by mouth, it can last up to four hours.

Common side effects include trouble sleeping, anxiety, headache, hallucinations, high blood pressure, fast heart rate, loss of appetite, and urinary retention. Serious side effects include stroke and heart attack. While probably safe in pregnancy, its use in this population is poorly studied. Use during breastfeeding is not recommended. Ephedrine works by inducing the release of norepinephrine and hence indirectly activating the α- and β-adrenergic receptors. Chemically, ephedrine is a substituted amphetamine and is the (1R,2S)-enantiomer of β-hydroxy-N-methylamphetamine.