Anti-Histamines – Their Meaning and Common Examples

Antihistamine is a simple medicine. This treats allergy symptoms by blocking the toxic effects of histamine. Antihistamines come in different forms such as pills, chewable tablets, capsules, liquids, injectable forms, eye drops, etc. Antihistamines are medicines often used to relieve symptoms of allergies. Some common examples are hay fever, hives, conjunctivitis, reactions to insect bites or stings, etc. Antihistamines are also used to oppose motion sickness and short-term treatment for insomnia disease. Claritin, Zyrtec, and Allegra are all best antihistamine. The patient can use antihistamine every day/ only when they have symptoms/ before being exposed to the things that cause allergy symptoms.

An allergy is usually not harmful. In some patients with allergies, the immune response is oversensitive. Antihistamines do not suppress the immune system. Allergies occur when the immune system thinks of a foreign substance. Common examples include pollen or pet dander, etc. This time histamines jump to action. This shows symptoms according to allergy. When their immune system recognises an allergen, they launch a response. Chemicals like histamines are released from the body. These chemicals cause allergy symptoms. When the body comes in contact with this allergy, reactions include swelling of nose tissues. This causes stuffy, running eyes and nose, itching of the mouth, hives(itchy rash on skin), etc. Antihistamines block histamines. Histamines are the attachment to receptors. Histamines cause increased fluid leakage from patients’ blood vessels with mucous production. This results in a runny nose. This prevents the compounds from carrying out their functions. This causes them to stop showing allergy symptoms. 

Antihistamines are a class of drugs commonly used to treat symptoms of simple/ complex allergies. These drugs help to treat conditions caused by chemicals called histamine. Histamines are the chemical created by your body’s immune system. These chemical compounds play a significant role in our body, like sleep and wakefulness. Antihistamines are commonly used by people who have allergic reactions to pollen and other allergens.

All people can’t take antihistamines. There are some limitations to the patients who have the following diseases-

• Glaucoma
• Trouble urinating
• Breathing problems (asthma, emphysema, chronic bronchitis, etc.)
• Thyroid disease
• Heart disease
• High blood pressure

Healthy adults rarely experience side effects from antihistamines. But, side effects can be a concern for older adults or people who have serious health problems. Sometimes 1st generation antihistamines may make you feel sleepy. Sleepness can affect your ability to drive. Patients can make it hard to think clearly. Alcohol can increase the risk of drowsiness. Antihistamines may cause patients’ mouths and eyes to feel very dry, abdominal pain and headaches, etc. Second-generation antihistamines are said to rarely cause side effects.

Allergy symptoms treated by Antihistamines-

Antihistamines help treat allergy symptoms. Examples of some symptoms are-

• Congestion
• Simple or extreme runny nose
• Sneezing
• Itching
• Swelling of the nasal passages
• Hives
• Skin rashes
• Itchy eyes
• Runny eyes

Time hacks to take antihistamines:

• Early in the morning
• Everyday use of antihistamines can help to keep these annoying symptoms under control
• Immediate use only when you have symptoms
• Before being exposed to allergies
• At night

Benefits of using antihistamines:

1. These medicines are frequently used to relieve symptoms from allergies like hay fever, hives, conjunctivitis, etc.
2. These are sometimes used to prevent motion sickness and as a short-term treatment for insomnia.
3. After treatment, the patient feels better and has better sleep.

The best antihistamine with an example of drugs:

•  Zyrtec (Cetirizine)
•  Allegra (Fexofenadine)
• Dimetane (Brompheniramine)
• Chlor-Trimeton (Chlorpheniramine)
• Tavist (Clemastine)
• Benadryl (Diphenhydramine)
• Optivar ( Azelastine eye drops)
• Astelin (Azelastine nasal sprays)
• Astepro (Azelastine nasal sprays)
• Palgic ( Carbinoxamine)
• Emadine (Emedastine eye drops)
• Vistaril ( Hydroxyzine)
• Livostin (Levocabastine eye drops)
• Xyzal ( Levocetirizine oral)

Negative/ side Effects of Antihistamines:

Antihistamines can cause more side effects on aged persons. The latest anti- histamines show lesser side effects. Some major side effects of antihistamines are-

• Dryness of mouth
• Drowsiness/ feeling drowsy
• Dizziness
• Nausea
• Vomiting
• Restlessness
• Moodiness (especially in children)
• Trouble peeing 
• Difficulty passing urine ( urinary retention)
• Stomach and gut upsets/ gastrointestinal discomfort
• Blurred vision
• Confusion
• Constipation

Conclusion

Antihistamines can cross the blood-brain barrier. It inhibits other functions of histamines. This disruption in the brain results in drowsiness. Loratadine (Claritin) and fexofenadine (Allegra) cause less drowsiness than first-generation antihistamines. Drowsiness is one of the significant side effects of some antihistamines. Some examples of such antihistamines are diphenhydramine (Benadryl) and doxylamine succinate, etc. These have strong sedating qualities. These medicines are active constituents of a thousand sleep piles. Antihistamines work best to relieve these symptoms. But, it is impossible to treat every symptom. After consulting your doctor, the patient can combine antihistamines and decongestants (treat nasal problem).