Antihistamines are a class of drugs used to suppress the effects of histamine in tissues to help relieve or prevent allergic symptoms and overproduction of gastric acid. Although antihistamines are available over the counter, it is recommended to seek pediatric consultation before taking them.
Antihistamines are not recommended for children below two years of age, and a prescription is mandatory for children below six years. The type of antihistamine, dosage, and duration may vary depending on the symptom, severity, age, health conditions, use of other medications, and bodyweight of children.
Read this post to know about the age limits, safety tips, medical uses, and side effects of antihistamines in children.
When Can You Give Antihistamines To Children?
Over-the-counter antihistamines can be given to children older than two years. Antihistamines are not recommended for children younger than two years and are not given to relieve cough and cold symptoms in children younger than six years (1). It is also recommended to seek a prescription for children younger than 12 years of age.
You should always ensure an OTC medication is safe for your child’s age group. Thus, always consult a pediatrician for the right prescription based on your child’s symptoms, body weight, and age.
Medical Uses Of Antihistamines
Antihistamines are also prescribed for several other medical conditions besides allergies, pruritus, and anaphylactic shock. H-1 blockers (check the “types” section for more information) are usually prescribed for the following conditions (2):
- Hay fever or allergic rhinitis
- Hives and other skin rashes
- Food allergies
- Allergic conjunctivitis
- Insects stings and bites
- Hypersensitivity to drugs
H-1 blockers are also preferred for treating the following conditions.
- Motion sickness
H-2 blockers help reduce stomach acid production. Therefore, they are prescribed for the following conditions.
- GERD (Gastroesophageal reflux disease)
- Zollinger-Ellison syndrome
- Gastric and duodenal ulcers
Safety Measures To Follow While Giving Antihistamines
Although antihistamines are available over-the-counter, it is recommended to consult a pediatrician if your child has persistent allergic symptoms. The doctor may prescribe more suitable antihistamines in appropriate doses.
The following tips may help you avoid unpleasant events associated with antihistamines (3).
1. Read the labels carefully: Ensure the product is safe for your child’s age. Although a product may be marked for children, it does not always mean that it is safe for all ages and situations. Learn about the dose recommendations according to the child’s age and body weight.
2. Do not give them to babies and toddlers: Do not give antihistamine to children younger than two years. OTC antihistamines are known to cause death in infants and toddlers. Thus, always follow a pediatric’s prescription to treat younger children.
3. Do not overdose: Do not give more than the recommended dose to your child. You may keep the antihistamine doses within the permitted daily limits to avoid other side effects.
4. Avoid double dosing: Read the contents of cough and cold products if your child is already taking antihistamines. Some cough and cold remedies contain antihistamines, and this may result in overdosing.
5. Keep them out of your child’s reach: You may keep antihistamines out of your child’s reach to avoid accidental consumption.
6. Keep an eye on your child’s activities: Do not let the child do activities requiring alertness since some antihistamines can cause drowsiness.
7. Avoid overuse of topical creams and ointments: Antihistamine creams and ointments should be applied on the skin as directed. The skin absorbs these, and overdosing can be toxic to the child.
8. Follow the correct prescription timings: Antihistamines should be given to the child as per the prescription since some medications may have their effects for a short time, and others may act for 12 to 24 hours. You may follow the timings mentioned in the prescription since some are given before the symptoms occur, such as before the season for seasonal allergies.
Children taking anticonvulsants for epilepsy should not be given antihistamines since this may cause drug interactions. Exercise caution when taking other drugs and medical conditions as well. You may seek a doctor’s advice if your child has liver or kidney problems or other chronic conditions.
Types Of Antihistamines
Antihistamines are available in various forms, including tablets, syrups, capsules, liquids, lotions, gels, creams, nasal sprays, and eye drops. Doctors may prescribe any of these depending on the illness.
Antihistamines can be divided into two main groups based on their effects. These include (2)
- Drowsy antihistamines that cause sleepiness or drowsiness, such as promethazine, hydroxyzine, and chlorpheniramine (Piriton).
- Non-drowsy antihistamines that are less likely to cause drowsiness or sleepiness, such as loratadine, fexofenadine, and cetirizine.
Based on the pharmacological action, antihistamines can be divided into two subtypes. These include (2)
- H-1 blockers or H-1 receptor antagonists
These are antihistamines used to manage allergy symptoms. They are further classified into first-generation antihistamines (approved from the 1930s) and second-generation antihistamines (1980s) based on when the US FDA approved them for use.
Examples of first-generation H-1 antihistamines are (2)
- Chlor-Trimeton (chlorpheniramine)
- Benadryl (diphenhydramine)
- Children’s Dimetapp Cold (brompheniramine)
- Vistaril (hydroxyzine)
- Dayhist (clemastine)
- Nolahist (phenindamine)
- Periactin (cyproheptadine)
- Dramamine (dimenhydrinate)
- Vicks NyQuil and other common cold and flu reliefs (doxylamine)
Second generation H-1 antihistamines may include (2):
- Zyrtec (cetirizine)
- Astelin (azelastine)
- Clarinex (desloratadine)
- Claritin (loratadine)
- Allegra (fexofenadine)
These medications are available on prescription and over the counter. You may seek pediatric consultation to know the proper dosage and duration of treatment.
- H-2 blockers or H-2 receptor antagonists
These are used to treat gastrointestinal problems such as acid reflux or GERD, vomiting, nausea, peptic ulcers, and gastritis.
A few examples of H-2 blockers are
- Axid (nizatidine)
- Pepcid (Famotidine)
- Tagamet HB (cimetidine)
- Zantac (ranitidine)
First-generation antihistamines block histamine receptors all over the body, including the brain and spinal cord, and cause drowsiness. In contrast, second-generation antihistamines do not cross the blood-brain barriers and do not usually cause drowsiness. Second-generation antihistamines are considered to be safer as they interact with fewer drugs and do not cause drowsiness.
Side Effects Of Antihistamines
Antihistamines may cause side effects in some children, and the side effects may vary depending on the type of antihistamine. The common side effects of drowsy antihistamines besides drowsiness include (4)
- Reduced coordination and responses (reactions)
- blurred vision
- Dry mouth
- Oliguria (reduced peeing)
The following side effects are often seen in non-drowsy antihistamines.
- Dry mouth
- Feeling sick
- Feeling drowsy (rare)
Do not use machinery or drive after taking antihistamines since it can affect a person’s alertness and responses. If your child has side effects after taking antihistamines, you may inform their healthcare provider.
Children with persistent allergic symptoms, gastrointestinal ulcers, or acid reflux require a pediatric visit for accurate treatment. Over-the-counter medications, including antihistamines, are not recommended for long-term management. Antihistamines only help relieve symptoms; they do not cure allergies.