Red warning triangle

18 June 2019

The warning triangle indicates that the medicine causes drowsiness, and that it can affect your ability to drive and use machines while on the medication.

The Danish Medicines Agency assesses if a certain medicine is to be labelled with a red warning triangle.

Only those medicines that significantly impair the ability to drive are labelled with a red warning triangle. And it is only indicative.

You can see which medicines are labelled with a red warning triangle on the Danish Medicines Agency’s list of drugs affecting the ability to drive.

It is very important to be aware that some medicines without a red warning triangle could still affect your ability to drive.

The warning triangle is used in Denmark, Norway, Finland and Iceland and is therefore not an international symbol.

If you buy medicine abroad, the warning label is likely to be different.

Drugs affecting the ability to drive – three degrees

Our assessment of whether or not to put a red warning triangle on the pack of a medicine is based on the medicine's effect and side effects, including if it is a medicine you administer yourself or if a doctor gives it to you – for example for anaesthesia during surgical procedures.

Our assessment decides which of the following three degrees of impairment to assign to a medicine.

  • No impairment to mild impairment

  • Small impairment to moderate impairment

  • Significant impairment

Examples of medicines with a red warning triangle

  • Opioids

  • Certain mild pain relievers

  • Antiepileptics

  • Medicines for anxiety

  • Tranquillisers

  • Cough remedies

  • Motion sickness medications

  • Anti-nausea medicines

  • Allergy and hay fever medicines

  • Migraine tablets

  • Certain weight-loss products

  • ADHD drugs

  • Any medicine containing more than 10 % alcohol

  • Sleeping tablets (don’t drive until the drug is out of your system)

Beware that not all drugs affecting the ability to drive have a red warning triangle

Some medicines without a red warning triangle might still affect your ability to drive and use machines.

You should therefore always read the package leaflet supplied with the medicine. It tells you about any precautions that you should take. Think twice if the medicine you take impairs your ability in any way.

Please take a note of these medicines, which don’t have a red warning triangle:

  • Eye drops which contain substances that dilate the pupils could impair your vision.

  • Medicines for high blood pressure can cause dizziness, discomfort and slower reactions as a result.

  • Insulin and medicines for diabetes may indirectly result in slower reactions. If you take too much medicine, your blood sugar could drop too low, and you can get dizzy and feel unwell, resulting in slower reactions.

  • Medicines for hay fever and allergy can result in slower reactions, so it's important to acknowledge how you feel. Remember also that hay fever alone can make you feel sleepy, thus resulting in slower reactions.

  • Dry cough medicines. These medicines affect the central nervous system, which means that they can make you drowsy.

  • Medicines for depression or other psychiatric disorders.

  • Several types of herbal medicines can also cause drowsiness, thus resulting in slower reactions. You should especially pay attention to medications that contain valerian.