How do rapid relief non-drowsy allergy medicines work?

non-drowsy allergy medicines
Medically reviewed by Richard Honaker M.D.


Millions of individuals worldwide suffer from allergies, which is a prevalent ailment.They manifest in various forms, such as sneezing, itching, runny nose, and watery eyes, which can significantly impact daily life. For many, traditional antihistamines used to alleviate these symptoms come with the unwanted side effect of drowsiness. However, non-drowsy anti-allergic medications offer a practical solution, allowing individuals to manage their allergies without compromising their alertness and productivity.  This blog will explore what non-drowsy allergy medicines are, how they work, who should take them, and which medications are best.

What is non-drowsy allergy medicine?

One type of antihistamine that is especially designed to reduce allergy symptoms without making people feel very sleepy is called non-drowsy allergy medication. Antihistamines are medications that act against the effects of histamine, which is the body’s reaction to an allergic reaction. Histamine can produce symptoms like runny nose, watery eyes, itching, and sneezing.

First-generation antihistamines, like diphenhydramine (Benadryl), can cross the blood-brain barrier, which often results in drowsiness and sedation as a side effect.

Second-generation antihistamines, often labeled as non-drowsy, have been developed to minimize these side effects. These medications are less likely to cross the blood-brain barrier, reducing their impact on the central nervous system and, therefore, causing less drowsiness.

Common non-drowsy allergy medicines include:

  • Cetirizine (Zyrtec): Can cause mild drowsiness in some people but is generally less sedating than first-generation antihistamines.
  • Loratadine (Claritin): Specifically designed to be non-drowsy and is effective for most people.
  • Fexofenadine (Allegra): Known for having minimal sedative effects and is another popular choice for non-drowsy relief.

These medications are typically taken once daily and are effective at managing symptoms of hay fever (allergic rhinitis), hives (urticaria), and other allergy-related conditions. They are available over-the-counter (OTC) in various forms, including tablets, liquids, and dissolvable tablets.

Need Personalized Allergy Treatment? Consult now to find the best non-drowsy medication for you.

Which medications are used to treat allergy symptoms?

There are many different ways to take allergy medications: tablets, liquids, nasal sprays, eyedrops, skin creams, inhalers, and injections. They are available with a prescription or over-the-counter. An overview of the various kinds of allergy drugs and their applications can be found here.

1. Antihistamines

Antihistamines stop histamine, a chemical released during an allergic reaction, to alleviate symptoms like runny nose, itchy or watery eyes, hives, and swelling.

Pills and Liquids

  • Sedating Antihistamines: Diphenhydramine, Chlorpheniramine
  • Non-Drowsy Antihistamines: Cetirizine (Zyrtec), Desloratadine (Clarinex), Fexofenadine (Allegra), Levocetirizine (Xyzal), Loratadine (Claritin)

Nasal Sprays

Antihistamine nasal sprays alleviate sneezing, itchy or runny nose, sinus congestion, and postnasal drip.

Side effects: Bitter taste, drowsiness, and fatigue.

  • Azelastine (Astelin, Astepro)
  • Olopatadine (Patanase)


Antihistamine eyedrops, available over-the-counter or by prescription, can relieve itchy, red, and swollen eyes. They may contain a combination of antihistamines and other medications.

Side effects: Headache, dry eyes. If the drops sting or burn, refrigerate them or use refrigerated artificial tears before application.

  • Ketotifen (Alaway, Zaditor)
  • Olopatadine (Pataday, Patanol, Pazeo)
  • Pheniramine and naphazoline (Visine, Opcon-A)

2. Decongestants

Decongestants provide sinus and nasal congestion rapid relief. They may result in adverse consequences like headaches, irritation, elevated blood pressure, and difficulty falling asleep.

Pills and Liquids

Oral decongestants, such the over-the-counter drug Sudafed (pseudoephedrine), relieve sinus and nasal congestion brought on by allergic rhinitis (hay fever).

For all-encompassing symptom relief, several oral allergy treatments include an antihistamine with a decongestant.

  • Pseudoephedrine (Sudafed)
  • Combination drugs: Loratadine and pseudoephedrine (Claritin-D), Fexofenadine and pseudoephedrine (Allegra-D), Desloratadine and pseudoephedrine (Clarinex-D), and Cetirizine and pseudoephedrine (Zyrtec-D)

Nasal Sprays and Drops

Nasal decongestant sprays and drops provide short-term relief for nasal and sinus congestion. However, using them for more than three consecutive days can lead to rebound congestion, where symptoms worsen.

Struggling with Allergy Symptoms? Consult now for expert advice and personalized allergy management.

3. Corticosteroids

Corticosteroids reduce inflammation associated with allergies.

Nasal Sprays

  • Budesonide (Rhinocort)
  • Fluticasone (Flonase)
  • Mometasone (Nasonex)
  • Triamcinolone (Nasacort)
  • Aerosol Formulas: Beclomethasone (Qnasl), Ciclesonide (Zetonna)


  • Beclomethasone (Qvar)
  • Budesonide (Pulmicort)
  • Ciclesonide (Alvesco)
  • Fluticasone (Flovent)
  • Mometasone (Asmanex)


  • Fluorometholone (Flarex)
  • Loteprednol (Alrex)
  • Prednisolone (Pred Forte)

Pills and Liquids

Skin Creams

4. Mast Cell Stabilizers

Mast cell stabilizers block the release of chemicals that cause allergic reactions.

Nasal Spray

  • Cromolyn (Nasalcrom)


  • Cromolyn (Crolom)
  • Lodoxamide (Alomide)
  • Nedocromil (Alocril)

5. Leukotriene Inhibitors

Leukotriene inhibitors block chemicals that cause allergy symptoms. Montelukast (Singulair) is used to treat hay fever.

6. Allergen Immunotherapy

Immunotherapy helps the body build tolerance to allergens through controlled exposure.


Administered weekly, then every two to four weeks.

Sublingual Immunotherapy (SLIT)

Tablets include dust mites (Odactra), short ragweed (Ragwitek), various grasses (Oralair), and Timothy grass (Grastek).

Biological Medications

Biological medications target specific immune reactions. Examples include:

  • Dupilumab (Dupixent) for allergic skin reactions
  • Omalizumab (Xolair) for asthma or hives

7. Emergency Epinephrine Shots

Used to treat anaphylaxis, these auto-injectors include:

  • Adrenaclick
  • Auvi-Q
  • EpiPen
Find Relief from Allergies Without Drowsiness! Consult now to explore the best non-drowsy options.

How does non-drowsy allergy medicine work?

Non-drowsy allergy medicines are typically second-generation antihistamines. They work by targeting the histamine receptors in your body, specifically the H1 receptors, to block the effects of histamine. Histamine is a chemical released by your immune system during an allergic reaction, leading to symptoms like itching, sneezing, runny nose, and watery eyes.

Mechanism of Action

  • Histamine Blockade: Non-drowsy antihistamines bind to the H1 receptors on cells, preventing histamine from attaching to these receptors. This stops histamine from causing allergic symptoms.
  • Blood-Brain Barrier: These medications are designed to minimally cross the blood-brain barrier. This characteristic reduces their impact on the central nervous system, thereby minimizing the sedative effects that are common with first-generation antihistamines.

“Non-drowsy, also known as second-generation antihistamines, are less soluble in lipids and consequently have reduced capability to penetrate the blood-brain barrier,” mentions William Harris, M.D., an allergist with Providence St. Joseph Hospital in Orange County, California. “Thus, they are less active in the brain, resulting in lower sedation.”

Who should take non-drowsy allergy medicine?

Non-drowsy allergy medications are ideal for individuals who need to manage their allergy symptoms while maintaining full alertness and productivity. This includes people who:

  • Work in environments where alertness is crucial, such as driving or operating heavy machinery.
  • Need to stay focused and attentive during the day, such as students or professionals.
  • Experience mild to moderate allergy symptoms that can be effectively managed with antihistamines.

What are the best non-drowsy antihistamines?

The best non-drowsy antihistamines are typically second-generation antihistamines due to their efficacy and reduced side effects. Some of the top choices include:

  1. Cetirizine (Zyrtec): Effective for 24-hour relief but may cause mild drowsiness in some individuals.
  2. Loratadine (Claritin): Known for minimal sedation and effective 24-hour relief.
  3. Fexofenadine (Allegra): Least likely to cause drowsiness and effective for both seasonal and perennial allergies.
  4. Desloratadine (Clarinex): A more potent derivative of loratadine with similar non-drowsy properties.

Which antihistamine causes the least drowsiness?

Among non-drowsy antihistamines, Fexofenadine (Allegra) is generally considered to cause the least drowsiness. It has a minimal sedative effect due to its reduced ability to cross the blood-brain barrier, making it a preferred choice for those needing to avoid drowsiness entirely.

Maximize Your Day, Minimize Allergies! Consult now to discuss effective, non-drowsy allergy medications.

When to See a Doctor About Your Allergy Symptoms

While over-the-counter non-drowsy antihistamines are effective for many people, it’s important to see a doctor if you experience:

  • Severe or persistent allergy symptoms that are not relieved by over-the-counter medications.
  • Side effects from allergy medications that interfere with your daily activities.
  • Symptoms that suggest a more serious condition, such as difficulty breathing or swelling of the lips and tongue.
  • The need for a personalized allergy management plan, especially if you have other health conditions or take multiple medications.

FAQs about non drowsy allergy medicine

What to take instead of benadryl for allergic reaction?

For those who need an alternative to Benadryl (diphenhydramine) that does not cause drowsiness, consider second-generation antihistamines. Options include:
Cetirizine (Zyrtec)
Loratadine (Claritin)
Fexofenadine (Allegra)
Desloratadine (Clarinex)

Is Benadryl a non-drowsy antihistamine?

No, Benadryl (diphenhydramine) is a first-generation antihistamine that typically causes drowsiness. Unlike second-generation antihistamines, it easily crosses the blood-brain barrier, leading to sedation. For non-drowsy alternatives, consider second-generation antihistamines like loratadine or cetirizine.

Are antihistamines good for cold symptoms?

While antihistamines can relieve symptoms like runny nose and sneezing associated with colds, they are primarily designed for allergy relief. They are not as effective for other cold symptoms such as cough or sore throat. Decongestants and other cold-specific medications are often more suitable.

What is the best non-drowsy allergy medicine for kids?

Several non-drowsy antihistamines are formulated for children. Popular options include:
Cetirizine (Zyrtec Children’s)
Loratadine (Children’s Claritin)
Fexofenadine (Children’s Allegra)
Always consult with a pediatrician before giving any medication to a child to ensure proper dosage and suitability.

Your Doctors Online uses high-quality and trustworthy sources to ensure content accuracy and reliability. We rely on peer-reviewed studies, academic research institutions and medical associations to provide up-to-date and evidence-based information to the users.

  • Kapoor, Rishi, Haley Halasz, and Saied Alhabash. “Recent Advances in the treatment of Allergic Rhinitis.” Journal of Student Research 11.2 (2022).
  • Setzer, Lauren. “Treatment of Allergic Rhinitis: Diphenhydramine vs. Fexofenadine.” (2023).
  • Pushpanjali, Pemmatte A., et al. “Electrochemical Analysis of the Antihistamine Drug Cetirizine at a Poly (Glutamine) Modified Carbon Nanotube Paste Electrode.” ChemistrySelect 8.31 (2023): e202300818.
  • Pakkasela, Johanna, et al. “Age-specific incidence of allergic and non-allergic asthma.” BMC pulmonary medicine 20 (2020): 1-9.

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