When Is the Best Time To Take Allergy Medicine?

The best time to take allergy medicine—antihistamines, decongestants, or steroids—is about two to four weeks before allergy season.1 The timing of allergy season varies from person to person and depends on your location and the time of year.2 Spring allergy season generally starts in February and ends during the early summer.2 Allergens, such as grasses, trees, and weeds, circulate during summer and fall.3

Should you take allergy medicine at night or in the morning? It might help to take allergy medicine at bedtime. Many notice their symptoms, including a runny or itchy nose, sneezing, coughing, or watery, itchy eyes, are worse during the early morning.45

Seasonal allergies, also called seasonal allergic rhinitis (hay fever), are common in the U.S. More than 67 million adults and 14 million children have seasonal allergies.6 Read on to learn when to start taking allergy medicine and other ways to avoid allergy symptoms.

When Should You Start Taking Allergy Medication?

Two to four weeks before allergy season begins is the general rule of thumb for when to start taking allergy medication.1 In contrast, antihistamines tend to work right away and do not need as long of a preparation period, Stanley Schwartz, MD, Ph.D., chief of medicine in the division of allergy, immunology, and rheumatology at the University at Buffalo, told Health.

The timing of allergy season depends on several factors, such as:2

• Location: Spring allergy season can start as early as January in warmer regions of the U.S. Plants typically pollinate earlier than average if there are mild temperatures during winter.
• Time of year: You can prepare for spring allergies by starting around Valentine’s Day, Christina Cruz, MD, an allergist and immunologist at Tufts Medical Center, told Health. In contrast, that date might be later in the year if you typically have summer or fall allergies. For example, mid-July or early September might be ideal if you are allergic to ragweed.
• Type of allergies: Trees, which pollinate earlier in the year, primarily drive spring allergy season.7 Grass pollen can cause symptoms in the late spring and summer. People who are allergic to ragweed or similar plants may have symptoms starting in the late summer and lasting through early winter.

How Often Should You Take It?

How often you take allergy medicine depends on the type. For example, you can take an antihistamine or use a nasal steroid spray every day to manage seasonal allergies.84 You might notice that your symptoms worsen during the early morning, around 4 a.m. to 6 a.m. In that case, it may help to take antihistamines at bedtime.4

You can use decongestants with an antihistamine or nasal steroid spray to manage symptoms. Some antihistamines are made with decongestants. Keep in mind that experts advise using a nasal spray decongestant for no longer than three days.9

What if I Miss a Dose?

Allergy medicines only reduce symptoms if you take them regularly.1 Take the missed dose as soon as possible to prevent symptoms from returning. You’ll want to skip the missed dose if it’s close to your next one. Do not double up on antihistamines, decongestants, or nasal steroid sprays if you miss a dose completely.101112

How Do You Know if You’re Taking the Right Medication?

Treatments available to manage symptoms can vary and often involve a fair amount of “trial and error,” said Dr. Cruz. There’s no evidence that the efficacy of antihistamines diminishes over time.13 Still, you might feel like you get better results when switching brands or medication types during allergy season.

“One brand may work particularly well on them for a certain amount of time, but then it kind of loses its efficacy the longer they use it. It’s not like a permanent tolerance develops,” said Dr. Cruz. “Your body kind of gets used to it, and it needs a break.”

It might be time to ask an allergist about allergy shots if changing up your medicine does not work. Allergy shots essentially get rid of allergy symptoms altogether, but they can take three or more years to be fully effective.14

Other Ways To Avoid Allergy Symptoms 

You may not be able to prevent seasonal allergies altogether. Still, there are several ways you can reduce allergy symptoms, in addition to medications, such as:15

• Avoid triggers: These include air pollution, tobacco smoke, and wind.
• Close windows and doors: This prevents pollen from entering your home, especially on high pollen days.
• Shower or bathe at night: This removes allergens from your hair and skin.
• Use air filters: These help remove some of the pollen inside your home.16
• Use sunglasses: This shields your eyes from allergens while outdoors.
• Wash your hands after petting animals: Pet dander is a common allergen.
• Wear a mask: Try wearing a mask while outdoors during the worst of your allergy symptoms.17
• Wrap your bedding and mattress: Use dust and mite-proof covers.

You can still enjoy the outdoors, even if you have seasonal allergies. Talk to an allergist if your symptoms do not improve or are difficult to manage. They can advise treatments and help develop a plan to control your symptoms.15