What do decongestants do? Uses
Decongestants also referred to as nasal decongestants, like Sudafed (which contains pseudoephedrine) and Sudafed PE (which contains phenylephrine) are over-the-counter medications used to treat and clear a stuffy nose and/or a blocked ear.
Clogging of the nose is caused by the swelling and inflammation of the nasal blood vessels, which leads to the formation of excess mucus and further clogging.
This can also give rise to the blocking of the Eustachian tube in the ear. The Eustachian tube connects the nasopharynx (throat) to the middle ear.
Due to this connection, any stuffiness and congestion in the nasopharynx will affect the pressure in the ears causing them to get blocked.
To put it differently:
Your nose is congested (overcrowded) due to the dilation of the blood vessels and the extra formation of the mucus in the nasal sinuses.
This results in blockage of your nose, which causes a lot of discomforts while breathing. This is one of the common symptoms of allergy and the cold
Decongestion is a process by which the decongestants relieve the congestion that has caused your nose to get blocked and the nasal sinuses to be inflamed.
How do decongestants work?
Most decongestants contain pseudoephedrine or phenylephrine as the active ingredient. Nasal sprays and nasal drops contain oxymetazoline.
They work to clear the nasal cavity by narrowing the blood vessels and reducing the swelling of the enlarged mucous membranes in the nose, throat, and sinuses.
This helps to drain the secretions of the nasal sinuses and open the clogged nasal passage. It also helps to clear the obstructed Eustachian tube in the ear opening up the blocked ears as well.
This action of the decongestant, which helps to clear and open the clogged nose and the blocked ears is called decongestion. It allows easy flow of air during breathing.
Decongestants do not treat the underlying cause or shorten the duration of the common cold. They merely act to give short-term relief from the symptoms of a blocked nose or ear.
The underlying causes of a blocked nose or ear include:
- An allergy reaction for which antihistamines and steroids may also be necessary
- A viral infection that will resolve on its own after a few days
- A bacterial infection for which antibiotics may also be necessary
Among the vast number of decongestants available for oral use, the most commonly used decongestant is pseudoephedrine.
Other examples include:
Short-acting nasal decongestants
- ephedrine (banned in U.S.)
- levmetamfetamine or L-desoxyephedrine (Vicks Vapo Inhaler)
- naphazoline (Privine)
- phenylephrine (Neo-Synephrine)
- propylhexedrine (Benzedrex Inhaler)
Long-acting decongestants (action of 8 to 12 hours)
- xylometazoline (Triaminic Decongestant Spray Nasal & Sinus Congestion)
- oxymetazoline (Afrin, Vicks Sinex, Zicam Nasal Gel)
For the list of oral and nasal over the counter decongestants, you could read at drugs.com
About pseudoephedrine and phenylephrine
Pseudoephedrine (eg. Sudafed) can be converted into methamphetamine. The U.S. Senate, therefore, passed a bill in 2005 restricting its sale. Methamphetamine is chemically similar to amphetamine, which is a highly addictive drug due to its stimulating effect on the nervous system. In some states, a prescription is required to purchase decongestants containing pseudoephedrine.
Phenylephrine. As a result, manufacturers have started using phenylephrine (eg. Sudafed PE) as an ingredient in decongestants. Phenylephrine, however, is less effective as a nasal decongestant and has a shorter time of action. It, therefore, has to be taken every four hours.
Forms of decongestants
Over the counter decongestants are available as:
- Oral decongestants in the form of tablets and capsules contain pseudoephedrine or phenylephrine. Brand names: Sudafed and Afrinol. Sustained-release tablets are also available, which are usually taken once a day.
- Nasal decongestant sprays contain phenylephrine, oxymetazoline, tramazoline, or xylometazoline. Brand names include Afrin, Neo-Synephrine
- Nasal decongestant drops contain ephedrine, or oxymetazoline, or xylometazoline. Brand name includes Otrivin nasal drops
- Nasal inhalers. Brand name includes Benzedrex
- Flavored powders to dissolve in hot water
Formulations of decongestants in combination with antihistamines are also available. They work well and are used to treat nasal congestion (clogged nose), frequent sneezing, and a running nose caused by allergic colds and hay fever. Examples include Allegra-D
Side effects and precautions for use
Being over-the-counter medicines and available without a prescription, it is essential that you read the instructions on the label before you start using decongestants.
Tablets and capsules are taken 3 to 4 times daily for not more than seven days at a time. This is because long-term use can increase the stuffiness in the nose. This is called rebound congestion.
Long-term use of decongestants can also cause side effects like insomnia, anxiety, fine tremors, headache, loss of appetite, fast heart rate, palpitation, high blood pressure, and an enlarged prostate.
Similarly, nasal sprays and drops should not be used for more than three days at a time for fear of inducing rebound congestion. Overuse can destroy the nasal mucosal lining, which helps to drain the nasal sinuses. In such situations, your nose becomes more stuffed up when you stop using the nasal drops.
You tend to use the nasal decongestant drops more for relief and a vicious cycle develops. Therefore, be wary when you are using the following nasal decongestants to avoid developing rebound congestion.
- Afrin (oxymetazoline)
- Sudafed (pseudoephedrine)
- Phenylephrine (Sudafed PE or Sudogest PE)
Contraindications for OTC decongestants
- Decongestants in any form are not safe for use in babies and children less than six years old in view of their side effects.
- Long-acting tablets or capsules are not recommended for use in children under 12 years old.
You must, therefore keep the medicine out of reach of the children.
Oral and topical nasal decongestants are contraindicated and not safe for use in:
- Pregnancy because they constrict the blood vessels of the uterus, which reduces the blood supply to the fetus. This can cause congenital anomalies in the fetus.
- Lactation (breastfeeding) because pseudoephedrine has been shown to reduce the milk volume in the mother. Furthermore, decongestants cause irritability, insomnia (difficulty in sleeping), and tachycardia (increased heart rate) in the baby.
- Patients with heart problems, because they increase the workload on the heart
- Diabetes because they can increase blood sugar by inhibiting the secretion of insulin, decrease the uptake of glucose by the peripheral tissue cells, and by stimulating the breakdown of glycogen in the liver.
- High blood pressure patients because they increase blood pressure due to their vasoconstrictor effect
- Thyroid disease because they increase the risk of side effects
- Men with an enlarged prostate should avoid decongestants because of their narrowing effect on the blood vessels. This mechanism helps to fight the nasal stuffiness but can worsen the problems of men with benign prostate hyperplasia (BPH) making urinating more difficult and worsening of the urine stream.
- In patients with Chronic closed-angle glaucoma (increased ocular pressure), topical decongestant eye drops are contraindicated because decongestants can cause dilation of the pupils, which can precipitate an acute glaucoma attack
Avoid taking decongestants with these medicines
Decongestants can interact with other medicines you may be taking. They may decrease the therapeutic effect of the medicines or can potentially increase the risk of side effects.
Such medicines include:
- Blood pressure medicines such as beta-blockers, calcium channel blockers, and methyldopa because pseudoephedrine in the decongestant decreases the efficacy of these hypertension drugs
- Medicines for asthma
- Diet pills
Avoid drinking too much caffeine because this will increase the risk of side effects. You may feel restless or you may find it difficult to go to sleep. Caffeine-containing items include tea, coffee, and aerated cold drinks.
Where natural remedies score
If for some reason, you are not able to take OTC decongestants, you should go in for natural remedies. Google them and you will have a wide variety of choices.
Though not so fast and effective, natural decongestants do work. Steam inhalation three or four times a day can also clear your nasal passages effectively.
When to seek Doctor’s help?
You should see your doctor when
- You’ve been taking self-medication for your stuffy nose and cold for one week with the over-the-counter decongestants and not getting the desired effect
- You develop pain over the face, especially over the cheeks and the forehead (that’s where the sinuses are located)
- Persistent headache
- Your nasal discharge turns yellowish indicating superimposed bacterial infection
- You develop a fever.