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Contac Cold Side Effects

Generic Name: pseudoephedrine

Note: This page contains information about the side effects of pseudoephedrine. Some of the dosage forms included on this document may not apply to the brand name Contac Cold.

For the Consumer

Applies to pseudoephedrine: oral capsule, oral capsule extended release, oral capsule liquid filled, oral liquid, oral solution, oral suspension, oral syrup, oral tablet, oral tablet chewable, oral tablet extended release

In addition to its needed effects, some unwanted effects may be caused by pseudoephedrine (the active ingredient contained in Contac Cold). In the event that any of these side effects do occur, they may require medical attention.

Severity: Moderate

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

Rare - more common with high doses
  • Convulsions (seizures)
  • hallucinations (seeing, hearing, or feeling things that are not there)
  • irregular or slow heartbeat
  • shortness of breath or troubled breathing
Symptoms of overdose:
  • Convulsions (seizures)
  • fast breathing
  • hallucinations (seeing, hearing, or feeling things that are not there)
  • increase in blood pressure
  • irregular heartbeat (continuing)
  • shortness of breath or troubled breathing (severe or continuing)
  • slow or fast heartbeat (severe or continuing)
  • unusual nervousness, restlessness, or excitement

Minor Side Effects

Some of the side effects that can occur with 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:
  • Nervousness
  • restlessness
  • trouble in sleeping
Less common:
  • Difficult or painful urination
  • dizziness or light-headedness
  • fast or pounding heartbeat
  • headache
  • increased sweating
  • nausea or vomiting
  • trembling
  • unusual paleness
  • weakness

For Healthcare Professionals

Applies to pseudoephedrine: compounding powder, oral liquid, oral suspension extended release, oral tablet, oral tablet chewable, oral tablet extended release


The most commonly reported adverse effects have included cardiovascular and (e.g. elevated blood pressure, tachycardia, or arrhythmias), CNS stimulation (e.g. restlessness, insomnia, anxiety, tremors, and rarely hallucinations), skin rashes, and urinary retention.[Ref]


Frequency not reported: Tachycardia, palpitations, arrhythmia, hypertension, impaired circulation to the extremities[Ref]

Nervous system

Frequency not reported: Headache, tremor


Frequency not reported: Dry mouth, nausea, vomiting


Frequency not reported: Hypersensitivity reactions including cross-sensitivity with other sympathomimetic[Ref]


Rare (less than 0.1%): Hallucinations
Frequency not reported: Restlessness, insomnia, sleep disturbances, anxiety, excitability[Ref]


Frequency not reported: Urinary retention, especially in men with prostatic enlargement


Frequency not reported: Angle-closure glaucoma


Frequency not reported: Skin rashes, fixed drug eruption in the form of erythematous nodular patches[Ref]


Post marketing reports: False-positive amphetamine immunoassay[Ref]

False-positives can occur far below the published threshold indicating that cross-reactivity in human specimens is sometimes greater than the limits reported.[Ref]


1. "Product Information. Sudafed (pseudoephedrine)." Glaxo Wellcome, Research Triangle Park, NC.

2. Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0

3. Cerner Multum, Inc. "Australian Product Information." O 0

4. Depriest AZ, Knight JL, Doering PL, Black DL "Pseudoephedrine and false-positive immunoassay urine drug tests for amphetamine." Pharmacotherapy (2012):

Not all side effects for Contac Cold may be reported. You should always consult a doctor or healthcare professional for medical advice. Side effects can be reported to the FDA here.

Disclaimer: Every effort has been made to ensure that the information provided is accurate, up-to-date and complete, but no guarantee is made to that effect. In addition, the drug information contained herein may be time sensitive and should not be utilized as a reference resource beyond the date hereof. This material does not endorse drugs, diagnose patients, or recommend therapy. This information is a reference resource designed as supplement to, and not a substitute for, the expertise, skill , knowledge, and judgement of healthcare practitioners in patient care. The absence of a warning for a given drug or combination thereof in no way should be construed to indicate safety, effectiveness, or appropriateness for any given patient. does not assume any responsibility for any aspect of healthcare administered with the aid of materials provided. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the substances you are taking, check with your doctor, nurse, or pharmacist.