How to go about choosing the correct antihistamine for your allergies
When someone is experiencing a seasonal allergy, most doctors (and previous Health24 articles) will suggest an antihistamine.
During an allergic reaction, your body releases histamine, a compound that is produced by cells as a mediator of the inflammatory and hypersensitivity responses. As soon as histamines are released into the body, they cause inflammation, which in turn causes your allergy symptoms, whether it’s coughing, congestion, sneezing or itching.
One of the most effective ways to block these histamines is by taking antihistamines. This medication reduces or blocks the histamines, which will reduce your allergy symptoms. Antihistamines were developed more than 70 years ago and are readily available on the market – in fact, there are so many that you may struggle to choose the right one. Here’s what you should know:
1. Choose the right format
Antihistamines are available in the form of nasal sprays, eye drops, pills or tablets. You need to choose one according to your specific allergy. The pills and tablets will help with itching, sneezing and a runny nose, while a nasal spray will help alleviate congestion and post-nasal drip.
Talk to your doctor or pharmacist. Based on your symptoms, they will be able to tell you what will work best for you. Some medications combine antihistamines with a decongestant, which helps to reduce the fluid in your nose.
Decongestants should only be taken when you really need them, as they can increase your blood pressure. Don’t choose a combination if you don’t have nasal decongestion.
2. You might need a prescription
While normal antihistamines are available over the counter, more severe forms of allergies may require a prescription from your doctor. If none of the over-the-counter brands helps alleviate your symptoms, it may be time to visit your doctor.
3. Get the most out of your medicine
You need to know that antihistamines are more effective when taken before symptoms appear. Most people only approach their pharmacist for medication when their symptoms are already in full swing, but these work much better if taken well before heading outdoors or anywhere else where you might be exposed to your trigger allergens. Read the instructions carefully and stick to the recommended dosage.
4. Know the ingredients
Not all antihistamines are the same and may contain a combination of ingredients and components to target different symptoms. In the past, the biggest concern for most people was the drowsiness caused by antihistamines as a side effect. Nowadays, however, antihistamines are formulated to be either "drowsy" or "non-drowsy", but in certain people some of the non-drowsy versions may still cause a level of drowsiness.
According to Dr Adrian Morris, our resident allergy expert, older antihistamines such as chlorpheniramine and Phenergan cross into the brain and make you drowsy. More modern antihistamines like loratadine and fexofenadine do not cross into the brain and therefore result in less drowsiness. Sometimes, though, drowsiness can be an asset as it helps to induce sleep at night.
Be sure to speak to your doctor or pharmacist if you are concerned about side-effects, especially if you need to concentrate or if operate heavy machinery as part of your job.
5. Keep other medical conditions in mind
While antihistamines are generally safe, they can clash with other prescription medicine such as the antibiotic erythromycin. Disclose to your doctor or pharmacist if you have a chronic illness or if you're pregnant or breastfeeding.
Questions to ask
Are your symptoms driving you bonkers? Here’s what you need to ask your pharmacist:
- What are the side-effects of this antihistamine?
- Will an over-the-counter antihistamine help me, or should I rather go to the doctor?
- How long/how often should I take this antihistamine?
- Are there any medications I should avoid while taking my antihistamine?
- Are my symptoms actually allergies, or could it just be a common cold? Not sure? You might want to read this Health24 article.
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