Disclaimer: This article is for informational purposes only and does not constitute medical advice. It is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of a physician or other qualified health provider with any questions you may have regarding a medical condition.
Overview
Reactine is a brand name for cetirizine, a second-generation antihistamine. It is taken once a day to relieve allergy symptoms. It can make some people drowsy.
Health Canada has authorized Reactine for hay fever (seasonal allergic rhinitis), year-round allergic rhinitis and chronic hives. The 5 mg and 10 mg strengths are sold without a prescription as tablets, tablets that melt in the mouth, liquid gels and a syrup. A 20 mg tablet is available by prescription only.
Reactine is sold without a prescription in Canada. If your symptoms do not improve, or you are not sure it is safe for you, BC residents can speak with a BC-licensed doctor by phone through Avee Health.
In Canada, Reactine is used in adults and children 12 years and over to relieve:
- Symptoms of seasonal and year-round allergic rhinitis, such as sneezing, a runny or stuffy nose, post-nasal drip, an itchy nose or throat, and watery or red eyes
- Chronic hives (chronic idiopathic urticaria), including the itching
In children 2 to 11 years, it is used for the symptoms of seasonal allergic rhinitis (hay fever) and for itching from allergic skin reactions such as hives.
Reactine treats symptoms. It does not cure allergies, and it is not a treatment for a severe allergic reaction (anaphylaxis). Call 911 for trouble breathing, throat swelling or fainting.
Cetirizine
Second-generation antihistamine
allergy
Over-the-counter
Available
How Reactine Works
During an allergic reaction the body releases histamine, which causes sneezing, a runny nose, itchy watery eyes and hives. Cetirizine is an antihistamine that blocks histamine and eases these symptoms.
After a single dose, it starts to work within 20 minutes in half of people and within 60 minutes in 95% of people. The effect lasts at least 24 hours, so it is taken once a day.
Dosage Instructions of Reactine
Follow the package directions. Reactine comes in several strengths and forms, so check the label of your product. The usual doses are:
- Adults and children 12 years and over: 5 mg or 10 mg once a day (one or two 5 mg tablets, or one 10 mg tablet or liquid gel)
- Adults 65 and over: 5 mg once a day
- Children 6 to 11 years: 10 mg once a day (one 10 mg tablet or 10 mL of syrup), or 5 mg in the morning and 5 mg in the evening
- Children 2 to 5 years: 5 mL of syrup (5 mg) once a day, or 2.5 mL in the morning and 2.5 mL in the evening
- Children under 2 years: only if a doctor advises it
Take it with or without food. Do not take more than the dose on the label. If the non-prescription strengths do not give enough relief, a doctor can prescribe up to 20 mg a day.
People with moderate kidney or liver problems should start with 5 mg a day. Ask a doctor or pharmacist first.
How long to take it: children should not take Reactine for more than 14 days unless a doctor directs it. Adults should ask a doctor before using it long term.
Missed dose: skip it and take your next dose at the usual time. Do not take two doses at the same time.
Storage Instructions
Store at 15°C to 30°C. Keep Reactine Allergy Liquid Gels away from high humidity and heat above 40°C, and protect them from light. Keep out of the reach of children.
Side Effects of Reactine
In clinical trials of doses up to 10 mg a day, the most common effects were:
- Drowsiness: 9.6% with cetirizine, compared with 5.0% with placebo
- Dry mouth: 2.1%, compared with 0.8% with placebo
- Headache: 7.4%, compared with 8.1% with placebo, so it was no more common than with placebo
Drowsiness is more likely at higher doses and is usually mild to moderate. At the prescription dose of 20 mg a day, 23.9% of people had drowsiness, compared with 7.7% with placebo. In children's trials, drowsiness affected 1.9% at 5 mg and 4.2% at 10 mg, compared with 0.8% with placebo.
Rare effects reported since Reactine came on the market include trouble passing urine, blurred vision, tremor, and itching after stopping the medicine.
Get medical help right away if you have:
- Signs of a serious allergic reaction, such as trouble breathing or swelling of the face, lips or throat
- A widespread rash with small pus-filled bumps and fever
- A seizure or fainting
- Yellow skin or eyes, or dark urine, which can be signs of liver problems
Important Safety Information About Reactine
- Do not use Reactine if you are allergic to cetirizine, hydroxyzine or similar piperazine medicines, or any ingredient in the product.
- Do not use it if you have severe kidney impairment (kidneys that work very poorly).
- Drowsiness: if you feel drowsy, do not drive or use machinery. Avoid alcohol and other products that cause drowsiness.
- Pregnancy: do not use Reactine unless a doctor advises it. There are no adequate studies in pregnant women.
- Breastfeeding: not recommended unless a doctor directs it.
- Kidney or liver problems, and adults 65 and over: start with 5 mg a day. Occasional rises in liver blood tests have been reported with cetirizine.
- Children: do not give it to a child under 2 unless a doctor advises it, or for more than 14 days unless a doctor directs it.
- Do not take more than the label dose. Use it long term only on a doctor's advice.
Drug Interactions
Tell your pharmacist about everything you take, including non-prescription products.
- Alcohol and medicines that cause drowsiness, such as sleep aids, anti-anxiety medicines, antidepressants, muscle relaxants, prescription pain medicines and other antihistamines: Reactine should not be used with them, because alertness can drop further.
- In studies, usual doses of cetirizine did not add to the impairment caused by alcohol or diazepam. The advice to avoid them still applies.
- No clinically significant interactions were found with theophylline, pseudoephedrine, cimetidine, erythromycin or ketoconazole.
Brands & DIN Number of Reactine
Brand Names
Reactine
Key Takeaways
- 1Reactine is cetirizine, a second-generation antihistamine for hay fever, year-round allergies and hives.
- 2The 5 mg and 10 mg strengths are sold without a prescription in Canada. The 20 mg tablet needs a prescription.
- 3The usual dose for adults and children 12 and over is 5 mg or 10 mg once a day. Adults 65 and over take 5 mg.
- 4It can cause drowsiness: 9.6% of people in clinical trials, compared with 5.0% with placebo. Do not drive if you feel drowsy.
- 5Avoid alcohol, sleep aids and other medicines that cause drowsiness while you take it.
- 6Do not use it with severe kidney impairment. People with moderate kidney or liver problems should start with 5 mg a day.
- 7Do not use it during pregnancy or while breastfeeding unless a doctor advises it.
Frequently Asked Questions
Do I need a prescription for Reactine in Canada?
How much does Reactine cost in Canada, and does BC PharmaCare cover it?
Does Reactine make you drowsy?
How long does Reactine take to work?
Can I drink alcohol while taking Reactine?
Can I take Reactine while pregnant or breastfeeding?
What is the difference between Reactine and Claritin?
When should I talk to a doctor?
Avee Editorial
Avee Editorial Team