Adult meltus chesty coughs with congestion (Guaifenesin, pseudoephedrine)

How does it work?

Adult meltus chesty coughs with congestion linctus contains two active ingredients, guaifenesin and pseudoephedrine hydrochloride.

Guaifenesin is a type of medicine called a cough expectorant. Expectorants are used to treat a productive or chesty cough, in which phlegm is coughed up.

Expectorants such as guaifenesin are thought to work by stimulating receptors in the stomach, causing a reflex increase in the volume of fluid produced in the airways. This decreases the thickness of the secretions in the airways, thus loosening phlegm and making it easier to cough up.

Pseudoephedrine is a type of medicine called a decongestant. It works by acting on alpha receptors that are found in the walls of blood vessels in the linings of the nasal passages and sinuses. It causes these blood vessels to contract and narrow, thereby decreasing blood flow into the linings of the nose and sinuses. This reduces the feeling of congestion and also reduces the production of mucus.

Pseudoephedrine also has a weak effect on receptors in the lungs called beta 2 receptors. By acting on these receptors it causes the muscles in the airways to relax. This allows the airways to open, making breathing easier.

The combination of guaifenesin and pseudoephedrine in this medicine may be useful for relieving chesty coughs with associated nasal or sinus congestion.

What is it used for?

  • Chesty coughs and nasal congestion, eg associated with colds.


  • Do not exceed the recommended dose. If symptoms persist consult your doctor.
  • If you have any of the following symptoms you should consult your doctor so that your cough can be investigated further: coughing up phlegm that is green, rusty brown, yellow, blood-stained or foul smelling; shortness of breath, wheezing or difficulty breathing; chest pain; pain and swelling in your calf; sudden weight loss; recurrent night-time cough; or a long-term persistent cough.

Use with caution in

  • Decreased kidney function
  • Decreased liver function
  • Disease involving the heart and blood vessels (cardiovascular disease)
  • High blood pressure (hypertension)
  • Overactive thyroid gland (hyperthyroidism)
  • Enlarged prostate gland (prostatic hypertrophy)
  • Difficulty passing urine (urinary retention)
  • Diabetes
  • Raised pressure in the eye ball, eg glaucoma.

Not to be used in

  • Children under 12 years of age
  • Very high blood pressure (severe hypertension)
  • Severe coronary artery disease
  • People who have taken a monoamine-oxidase inhibitor antidepressant (MAOI) in the last 14 days.

This medicine should not be used if you are allergic to one or any of its ingredients. Please inform your doctor or pharmacist if you have previously experienced such an allergy.If you feel you have experienced an allergic reaction, stop using this medicine and inform your doctor or pharmacist immediately.

Pregnancy and Breastfeeding

Certain medicines should not be used during pregnancy or breastfeeding. However, other medicines may be safely used in pregnancy or breastfeeding providing the benefits to the mother outweigh the risks to the unborn baby. Always inform your doctor if you are pregnant or planning a pregnancy, before using any medicine.

  • The safety of this medicine in pregnancy has not been established. As with all medicines, it should be avoided during pregnancy unless considered essential by your doctor. Seek medical advice from your doctor, pharmacist or midwife before taking this medicine if you are pregnant.
  • This medicine passes into breast milk in amounts that are too small to be harmful to a nursing infant. However, as with all medicines, seek medical advice from your doctor or pharmacist before taking this medicine if you are breastfeeding.

Side effects

Medicines and their possible side effects can affect individual people in different ways. The following are some of the side effects that are known to be associated with this medicine. Because a side effect is stated here, it does not mean that all people using this medicine will experience that or any side effect.

  • Restlessness
  • Difficulty sleeping (insomnia)
  • Anxiety
  • Increased heart rate
  • Rash
  • Difficulty in passing urine (urinary retention)
  • False perceptions of things that are not really there (hallucinations)

The side effects listed above may not include all of the side effects reported by the drug's manufacturer.For more information about any other possible risks associated with this medicine, please read the information provided with the medicine or consult your doctor or pharmacist.

How can this medicine affect other medicines?

If you are already taking any other medicines, including herbal medicines and those bought without a prescription, you should check with your pharmacist before taking this medicine, to ensure that the combination is safe.

This medicine should not be used by people who are currently taking a monoamine oxidase inhibitor antidepressant, eg phenelzine, tranylcypromine, isocarboxazid or moclobemide, or who have taken one of these medicines in the last 14 days, as the combination could cause a dangerous rise in blood pressure (hypertensive crisis).

If pseudoephedrine is taken with any of the following the combination may cause an increase in blood pressure:

  • other decongestants (often found in non-prescription cough and cold remedies)
  • tricyclic antidepressants, eg amitriptyline
  • appetite suppressants
  • amphetamine-like stimulants.

Pseudoephedrine may reduce the effects of medicines to treat high blood pressure (antihypertensives). If you are taking medicines for high blood pressure you should not take this medicine.

Other medicines containing the same active ingredients

Robitussin for chesty coughs with congestion Sudafed expectorant