Types of Medicines Used to Treat Allergies

Allergies are life-threatening conditions if not treated properly. Fortunately, there are multiple drugs useful in treating these conditions.

Last update: October 07, 2021

The human body lives in balance with the materials of the environment. People have an immune system responsible for protecting the integrity of the body. However, you can react inappropriately. Fortunately, professionals have different types of medications to treat allergies.

Allergies or hypersensitivity reactions are result of a disproportionate response of the human body to foreign substances for the immune system, called allergens. In this way, the body initiates a complex chemical cascade that alters internal functions.

This entity can present with local or systemic symptoms.. Hives, runny nose, and shortness of breath are some of the most common symptoms. At present, antihistamine and decongestant medications are the most used in the control of allergies.

What are allergens and how do they affect the body?

Allergens are the molecules responsible for inducing hypersensitivity responses. These are substances that are found in the environment and are not harmful to everyone. In this sense, allergies are going to be conditioned by their own genetic and immune characteristics.

Studies claim that most allergens are protein in nature. They can come into contact with people through the respiratory tract, skin and mucous membranes, and even through the gastrointestinal tract. Some of the most common are the following:

  • Pollen.
  • Dust.
  • Pet dander.
  • Medicines.
  • Food.
  • Bites
  • Latex.

The route of entry of the allergen determines the type of harmful effects on the human body. Bronchial asthma, sinusitis, and rhinitis usually occur when the substance is inhaled. Contact of the allergen with the skin usually causes dermatitis and hives.

Types of medicines to treat allergies

The different types of drugs used in the treatment and control of allergies or antiallergics seek to counteract the mechanisms responsible for it. These drugs are intended to minimize the hypersensitivity reaction and, consequently, the clinical manifestations.

Anti-allergy medications are available in various forms for oral, inhalation, topical, ophthalmic, and intravenous administration. The drug, the dose and the time of use will depend on the severity of the symptoms and the response of the body to the treatment.

Hives usually appear after skin contact with an allergen from the environment.


Histamine is a chemical released by cells of the immune system in response to allergens. Mediates hypersensitivity reactions by binding to central and peripheral H1 receptors.

Antihistamines work by inhibiting the action of histamine in tissues. Consequently, they reduce allergic symptoms. Research suggests that desloratadine is one of the drugs with the highest affinity and inhibition of H1 receptors.

Cetirizine, chlorpheniramine, fexofenadine, and loratadine are some of the antihistamines for oral consumption that are usually sold without a prescription. Drowsiness, weakness, and tiredness are the most common adverse effects. Similarly, it is advisable not to consume alcoholic beverages during its administration.

Some nasal antihistamines are azelastine and olopatadine, useful in treating nasal congestion and sneezing. Side effects include a bitter taste in the mouth and feeling tired. Similarly, ophthalmic solutions are used in the treatment of allergic conjunctivitis, although they can cause dry eyes.

These medications should not be consumed before driving or working with heavy machinery, due to the drowsiness they generate. Its prescription during pregnancy must be done under strict medical supervision.


Decongestants are drugs that work by decreasing inflammation and reducing mucus secretion in the nose, sinuses, throat, and middle ear. They are one of the types of medications most used in the management of inhalation allergies, such as allergic rhinitis and sinusitis.

These drugs are available for oral consumption in pills and liquids, as well as for local administration in drops or sprays. Some oral decongestants like pseudoephedrine are available over the counter and often come in combination with antihistamines.

Nasal solutions, such as oxymetazoline, are the most used form of presentation for their quick relief. Nevertheless, its effect tends to last very little and promotes overuse. Decongestants can cause adverse effects such as headaches, increased blood pressure, insomnia, and irritability.

The use of these drugs is not recommended in people with high blood pressure., heart disease, diabetes, glaucoma, or hyperthyroidism. Children and pregnant women should only consume the drug under medical supervision.


Corticosteroids are a group of medications capable of reducing the exaggerated inflammatory response that usually accompanies allergies. They can be administered orally, inhaled, cutaneously and injected. Studies affirm that treatment with these compounds is carried out for prolonged periods and with staggered doses, given the chronicity of allergies.

Prednisone and methylprednisolone are oral presentations that are used in the systemic therapy of all types of allergies. Its excessive use can cause adverse effects, such as cataracts, hyperglycemia and growth disorders in children. For this reason, they should only be consumed under strict prescription and professional supervision.

Inhaled formulations are often combined with bronchodilators in the management of bronchial asthma. Beclomethasone and budesonide are some of the most used presentations. In addition, side effects are rare and include irritation of the oral mucosa and predisposition to oral yeast infections.

Fluorometholone and Lotoprednol are ophthalmic solutions that are used to relieve eye symptoms of allergies. On the other hand, topical corticosteroids, such as desonide and hydrocortisone, are useful in managing the itching, scaling, and redness of allergic urticarias.

These drugs are not recommended in patients with diabetes, systemic infections, psychiatric illnesses, osteoporosis, and gastric ulcers. Its use is usually limited in immunosuppressed people and those with heart disease.

Leukotriene inhibitors

Leukotrienes are chemicals released by the immune system that are involved in inflammation, mucus discharge, and bronchial constriction. Lleukotriene inhibitors work by binding to the receptors of these molecules, preventing its effect on the body.

They are among the types of medications most used to treat asthma due to allergies in mild and moderate cases. They are also widely useful in the control of sneezing, runny nose and nasal congestion. Currently, montelukast is one of the few leukotriene inhibitors approved for the treatment of seasonal allergic rhinitis.

Adverse effects of this group of drugs include headache, drowsiness, trouble sleeping, and an upset stomach. They are contraindicated during pregnancy, lactation and in patients with severe liver disease..

Mast cell stabilizers

These are drugs for local use that can be administered nasal and ophthalmic.. They inhibit the release of inflammatory mediators from mast cells. In this way, they contribute to reducing hypersensitivity reactions and associated symptoms.

Chromolin is an over-the-counter aerosol formulation used for nasal conditions. On the other hand, lodoxamide and nedocromil come in eye drops useful for the management of redness and itching of the eyes due to allergies.


Epinephrine or adrenaline is a medicine used only in the management of severe allergic reactions. It is generally used for anaphylactic conditions from bites, insect stings, foods, and medications. It is also useful in the control of superficial bleeding and cardiac arrest.

This substance is an endogenous epinephrine analog. It works by constricting blood vessels and relaxing the respiratory muscles. It comes as an automatic injection device and in bottles for subcutaneous or intramuscular administration.

Epinephrine injections are very useful in slowing down the progression of allergies, but they are not a substitute for medical treatment. For this reason, it is essential to seek care as soon as possible after its administration.

Epinephrine ampoules are used in hospitals to administer the drug by a rapid absorption route.

When to seek medical attention?

Allergies are conditions that evolve in a matter of minutes. These reactions are usually mild and are treated with over-the-counter medications. However, worsening symptoms indicate the need for immediate care.

Health professionals recommend not underestimating hypersensitivity reactions no matter how small. In addition, it is vital to seek emergency care for the manifestation of the following symptoms:

  • Shortness of breath and wheezing.
  • Intense stinging and redness of the skin.
  • Increased heart rate and weak pulse.
  • Confusion and loss of consciousness.

The doctor is the best ally when fighting allergic reactions

The diagnosis of hypersensitivity to certain substances can be unpleasant for most people and warrants several lifestyle changes. Ongoing collaboration with your GP is vital when choosing between the various types of allergy medications.

The health professional is the only one capable of recognizing the condition in detail and offer the best therapeutic options. For this reason, do not hesitate to consult your trusted doctor in the event of any strange signs or symptoms that make you suspect an allergy.

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