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cetirizine

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Brand names: Zyrtec

Second-Generation Antihistamine OTC

Cetirizine (Zyrtec) is an antihistamine medicine. It helps relieve allergy symptoms.

Drug Pricing (NADAC)

Generic Price

$0.02/unit

Generic Available

Yes (44 manufacturers)

Pricing data from NADAC (CMS), effective December 18, 2024. Compare all drug costs →

What it does

This medicine treats allergy symptoms.

Common side effects

Headache, Fatigue

Key warnings

Ask a doctor before use if you have liver or kidney disease.

How It Works

Cetirizine blocks histamine in your body. Histamine is a natural substance that causes allergy symptoms. By blocking it, cetirizine reduces these symptoms.

How to Take It

You can take this medicine with or without water. Chew or crush the tablets completely before swallowing. Children 2 to under 6 years old: Chew and swallow 1 tablet (2.5 mg) once a day. If needed, the dose can be increased to 2 tablets (5 mg) once a day, or 1 tablet (2.5 mg) every 12 hours. Adults and children 6 years and over: Chew and swallow 2 tablets (5 mg) or 4 tablets (10 mg) once daily depending upon severity of symptoms. Adults 65 years and over: Chew and swallow 2 tablets (5 mg) once daily.

Pregnancy & Breastfeeding

Ask a doctor if you are pregnant or breastfeeding before taking this medicine. It is not known if cetirizine will harm your unborn baby or pass into breast milk.

Missed Dose

If you miss a dose, take it as soon as you remember. Do not take more medicine than prescribed in a 24-hour period.

Storage

Store between 68° to 77°F (20° to 25°C). Do not use if the blister unit is torn or broken.

Side Effects (from patient reports)

Based on 101,043 FDA adverse event reports.

The medicine did not work
12,977
Tiredness
12,862
Pain
12,124
Skin rash
9,771
Using the medicine for a condition it is not approved for
9,340
Stomach upset
9,317
Hair loss
9,237
Rheumatoid arthritis
8,675
Systemic lupus erythematosus
8,466
Pemphigus
8,274

FDA Adverse Event Report Analysis

Detailed analysis of 72,729 reports from the FDA Adverse Event Reporting System (FAERS). Reports span 2004–2025.

Total Reports

72,729

Death-Related Reports

7,810

Hospitalization Reports

22,963

Top Indication

Product Used For Unknown Indication

Gender Distribution

Female 44,738 (71%)
Male 18,377 (29%)

Age Distribution

0–17 4,644
18–44 15,430
45–64 14,527
65–74 7,743
75+ 5,859

Most Reported Adverse Reactions (FAERS)

# Reaction Reports
1 DRUG INEFFECTIVE 12,976
2 FATIGUE 12,861
3 PAIN 12,124
4 RASH 9,771
5 OFF LABEL USE 9,340
6 ABDOMINAL DISCOMFORT 9,317
7 ALOPECIA 9,237
8 RHEUMATOID ARTHRITIS 8,675
9 SYSTEMIC LUPUS ERYTHEMATOSUS 8,466
10 PEMPHIGUS 8,274
11 SWELLING 7,934
12 HYPERSENSITIVITY 7,746
13 GLOSSODYNIA 7,743
14 PRURITUS 7,514
15 ARTHRALGIA 7,475

Reactions in Death Reports

OFF LABEL USE 2,219
FATIGUE 2,132
SYSTEMIC LUPUS ERYTHEMATOSUS 2,129
RASH 2,113
RHEUMATOID ARTHRITIS 2,110
GENERAL PHYSICAL HEALTH DETERIORATION 2,096
HYPERTENSION 2,093
INFUSION RELATED REACTION 2,089
HEPATIC ENZYME INCREASED 2,074
TYPE 2 DIABETES MELLITUS 2,070

Reactions in Hospitalization Reports

FATIGUE 4,029
OFF LABEL USE 3,670
PAIN 3,617
DYSPNOEA 3,442
RASH 3,316
ABDOMINAL DISCOMFORT 3,230
PYREXIA 3,190
ARTHRALGIA 3,148
MALAISE 3,023
NAUSEA 2,989

Source: FDA FAERS (Adverse Event Reporting System) FDA FAERS (Adverse Event Reporting System) Reports are voluntary and do not establish causation

Serious Warnings

Ask a doctor before use if you have liver or kidney disease. Children under 2 years of age should ask a doctor before use.

Known Drug Interactions

7.5 Drugs Without Clinically Significant Interactions with Efavirenz No dosage adjustment is recommended when efavirenz is given with the following: aluminum/magnesium hydroxide antacids, azithromycin, cetirizine, famotidine, fluconazole, lorazepam, nelfinavir, nucleoside reverse transcriptase inhibitors (abacavir, emtricitabine, lamivudine, stavudine, tenofovir disoproxil fumarate, zidovudine), paroxetine, and raltegravir.

Mechanism: These drugs do not interfere with how the body processes each other.

What to do: No dosage adjustments are needed if you take these two medicines together.

Common Questions

Can children take this medicine?
Yes, children 2 years and older can take this medicine. Ask a doctor for children under 2.
Can I take this with food?
Yes, you can take this medicine with or without food.
How often can I take this medicine?
Take this medicine once a day.
What should I do if I take too much?
Call a doctor or go to the nearest hospital emergency room.
Can I drive while taking this medicine?
This medicine may cause drowsiness. Be careful driving or operating machinery.
Can I take this medicine if I have kidney problems?
Ask a doctor before use if you have kidney disease.
Can I take this medicine if I have liver problems?
Ask a doctor before use if you have liver disease.
How long does it take for this medicine to work?
This medicine starts to work within one hour.
Can I take this with other allergy medicines?
Ask a doctor or pharmacist before taking this with other medicines.
What if my symptoms don't improve?
Talk to your doctor if your symptoms do not improve after taking this medicine.
What are the common side effects of cetirizine?
The most commonly reported side effects of cetirizine include Headache, Fatigue. Based on 101,043 FDA adverse event reports. Always consult your healthcare provider about potential side effects.
Does cetirizine interact with other medications?
Yes, cetirizine has 1 known drug interactions. Notable interactions include efavirenz/emtricitabine/tenofovir. Always inform your doctor about all medications you are taking.
What drug class is cetirizine?
cetirizine belongs to the Second-Generation Antihistamine drug class. It is available over the counter (OTC). This medicine treats allergy symptoms.
Is cetirizine safe during pregnancy?
Ask a doctor if you are pregnant or breastfeeding before taking this medicine. It is not known if cetirizine will harm your unborn baby or pass into breast milk. Always consult your healthcare provider before using any medication during pregnancy or breastfeeding.
Has cetirizine been recalled?
There are 2 recalls associated with cetirizine products. Tablet/Capsules Imprinted with Wrong ID. Check the recalls section below for full details and affected products.

Active Recalls

Class III September 12, 2025

Tablet/Capsules Imprinted with Wrong ID

JB Chemicals and Pharmaceuticals Ltd

Class II March 13, 2025

CGMP Deviations

Glenmark Pharmaceuticals Inc., USA

Related Medications in Second-Generation Antihistamine

Other drugs grouped near cetirizine — same-class peers and common alternatives.

Compare cetirizine vs azelastine side-by-side →

Medication Guides

Related Health & Safety Data

What the FDA Data Shows for cetirizine

The FDA label for cetirizine (sold under brand names such as Zyrtec) classifies it as an over-the-counter product in the Second-Generation Antihistamine class. This medicine treats allergy symptoms. Official labeling lists 2 commonly reported side effects, including Headache, Fatigue.

Post-market surveillance from the FDA Adverse Event Reporting System (FAERS) captures real-world experience. For this drug, FAERS contains 101,043 voluntary reports. The database also lists 1 documented drug interaction derived from FDA labeling, with the top-flagged interaction rated minor severity. NADAC pricing from CMS shows a generic unit cost of $0.02.

Report counts do not establish causation — a FAERS entry documents a temporal association, not proof that the drug produced the outcome. Widely prescribed medications naturally accumulate more reports than niche therapies, so raw totals must be interpreted alongside total exposure. Shortage status, recall history (currently 2 recall records on file), and patent information further shape supply and switching decisions. This page summarizes public FDA data for educational purposes only and is not a substitute for professional medical advice — always consult a licensed healthcare provider before starting, stopping, or changing any medication.

Data Sources

Drug labeling: FDA Drug Labels (SPL/DailyMed). Adverse events: FDA Adverse Event Reporting System (FAERS). Pricing: CMS National Average Drug Acquisition Cost (NADAC).

FAERS reports are voluntary and do not establish causation. Drug interactions are derived from FDA labeling and clinical references. Always consult a healthcare professional before making medication decisions.

Last updated: April 7, 2025

All federal data sources used on this page