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KS Aller-Tec D-12 Side Effects

Generic Name: cetirizine / pseudoephedrine

Note: This page contains information about the side effects of cetirizine / pseudoephedrine. Some of the dosage forms included on this document may not apply to the brand name KS Aller-Tec D-12.

For the Consumer

Applies to cetirizine / pseudoephedrine: oral tablet extended release

In addition to its needed effects, some unwanted effects may be caused by cetirizine / pseudoephedrine. In the event that any of these side effects do occur, they may require medical attention.

If any of the following symptoms of overdose occur while taking cetirizine / pseudoephedrine, get emergency help immediately:

Symptoms of overdose:
  • Changes in mood, irrational behavior, depersonalization hallucinations
  • convulsions (seizures)
  • extreme sleepiness or unusual drowsiness
  • fast, slow, pounding, or irregular heartbeat or pulse
  • feeling anxious
  • giddiness
  • headache
  • irritability
  • muscle weakness or tenderness
  • nausea
  • restlessness
  • shallow, irregular, fast, or slow breathing
  • sleeplessness or trouble in sleeping
  • abdominal and/or chest pain
  • thirst

Severity: Moderate

If any of the following side effects occur while taking cetirizine / pseudoephedrine, check with your doctor or nurse as soon as possible:

  • Breathing, troubled
  • back, leg, or stomach pain
  • blurred vision
  • bloody, cloudy, or dark urine, sudden decrease in amount of urine
  • black, tarry stools, diarrhea, light-colored stools
  • confusion
  • dizziness, feeling faint, or lightheaded
  • fever or chills
  • increased blood pressure
  • rapid weight gain
  • skin rash or hives
  • swelling of face, mouth, throat, fingers, glands, feet, and/or lower legs
  • stillbirth
  • twitching, twisting, or uncontrolled repetitive movements of the face
  • sudden sweating
  • vomiting blood, bleeding gums, nosebleeds, unusual bleeding or bruising
  • pale or yellow eyes or skin
  • unusual tiredness or weakness

Minor Side Effects

Some of the side effects that can occur with cetirizine / pseudoephedrine may not need medical attention. As your body adjusts to the medicine during treatment these side effects may go away. Your health care professional may also be able to tell you about ways to reduce or prevent some of these side effects. If any of the following side effects continue, are bothersome or if you have any questions about them, check with your health care professional:

More common:
  • Sleepiness or unusual drowsiness, extreme tiredness
Less common:
  • Dry mouth
  • weakness
  • Dizziness
  • sore throat

For Healthcare Professionals

Applies to cetirizine / pseudoephedrine: oral tablet extended release


Dermatologic side effects have included maculopapular and urticarial eruptions.[Ref]


Gastrointestinal side effects of cetirizine have included dry mouth (5.7%) and nausea or vomiting (2.2%). Pharyngitis, dyspepsia, and increased appetite have occasionally been reported.

Gastrointestinal adverse effects of pseudoephedrine have included anorexia and gastric irritation (5%). Dry mouth, nose, or throat have occurred in up to 15% of patients.[Ref]


Hepatic side effects have included rare liver function test abnormalities which resolved spontaneously following discontinuation of cetirizine therapy.[Ref]

Nervous system

Cetirizine appears to be more sedating than terfenadine, astemizole, and loratadine.[Ref]

Nervous system side effects of cetirizine administration have included headache (16%), fatigue (5.6%), and somnolence (5% to 20%). Somnolence tends to be dose-related and generally occurs more frequently with doses higher than 10 mg per day. Other nervous system side effects include dizziness (1.8%), insomnia (1.5%), and nervousness (1.1%). Post marketing reports have included aggression reaction and convulsions.

Nervous system side effects of pseudoephedrine have included insomnia in up to 30% of patients. Tremor, anxiety, nervousness, and headache have also been reported.[Ref]


Respiratory side effects have included wheezing, coughing, bronchitis, sinusitis, and asthma.[Ref]


Hypersensitivity reactions have included fixed drug eruptions with pseudoephedrine use.[Ref]


Cardiovascular side effects have included tachycardia. Some patients have developed hypertension and/or arrhythmias.[Ref]


General side effects have included epistaxis (1.1%) and accidental injury (1.1%).[Ref]


1. "Product Information. Zyrtec (cetirizine)." Pfizer US Pharmaceuticals, New York, NY.

Not all side effects for KS Aller-Tec D-12 may be reported. You should always consult a doctor or healthcare professional for medical advice. Side effects can be reported to the FDA here.

More about KS Aller-Tec D-12 (cetirizine / pseudoephedrine)

Consumer resources

Other brands: Zyrtec-D, All Day Allergy-D

Professional resources

Related treatment guides

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