Guaifenesin

Guaifenesin belongs to the pharmacological class of expectorants, which helps in relieving the conditions of chest congestion and cough.

Guaifenesin is absorbed via the Gastrointestinal tract. Guaifenesin achieves a volume of distribution of 116L. Guaifenesin undergoes metabolism, and the primary metabolites of the substance are β-(2-methoxyphenyl)-lactic acid and the demethylated hydroxyguanosine citrate. The route of elimination of Guaifenesin is majorly through urine.

The common side effects of Guaifenesin are hives, diarrhea, dizziness, stomach pain, headache, nausea or vomiting, and skin rash.

Guaifenesin is found to be available in the form of liquid, granules, and immediate-release tablets.

Guaifenesin is available in the U.S., Canada, E.U., India, Australia, and Japan.

Guaifenesin belongs to the pharmacological class of expectorants, which helps in relieving the conditions of chest congestion and cough.

Guaifenesin acts as an expectorant by increasing the volume as well as reducing the viscosity of secretions in the trachea and bronchi. It might aid in the flow of the respiratory tract secretions, thereby allowing ciliary movement in order to carry the loosened secretions upward toward the pharynx.

Guaifenesin had been approved for relieving symptoms as well as also for the treatment and maintenance of episodes of chest congestion and cough.

The onset of action of Guaifenesin is said to be within 30 minutes. The duration of action of Guaifenesin is 4-6 hours.

Guaifenesin is available in liquid, granules, and immediate-release tablets.

Guaifenesin can be used in the treatment of the following conditions:

• Chest congestion
• Cough

Guaifenesin can help to relieve symptoms and also for the treatment and maintenance of chest congestion and cough.

Guaifenesin is approved for the treatment in the following clinical indications/conditions:

• Chest congestion
• Cough

Liquid: To be swallowed directly

Granules and Immediate-release tablets

To be swallowed as a whole with water.

Liquid:

Children aged 2 years to <4 years: Limited data available: 50 to 100 mg every four hours as needed; do not exceed six doses in 24 hours (Ref).

Children aged 4 to <6 years: 50 to 100 mg every 4 hours as needed; do not exceed six doses in 24 hours.

Children aged 6 years to <12 years: 100 to 200 mg every 4 hours as needed; do not exceed six doses in 24 hours

Children aged ≥12 years and Adolescents: 200 to 400 mg every four hours as needed; do not exceed six doses in 24 hours.

Granules:

Children aged 4 years to <6 years: 100 mg every four hours as needed; do not exceed six doses in 24 hours

Children aged 6 years to <12 years: 100 to 200 mg every four hours as needed; do not exceed six doses in 24 hours

Children aged ≥12 years and Adolescents: 200 to 400 mg every four hours as needed; do not exceed six doses in 24 hours.

Immediate-release tablet:

Children aged 6 years to <12 years: 200 mg every four hours as needed; do not exceed six doses in 24 hours

Children aged ≥12 years and Adolescents: 400 mg every four hours as needed; do not exceed six doses in 24 hours.

Extended-release tablet: Children aged aged ≥12 years and Adolescents: 600 mg to 1,200 mg every twelve hours as needed; do not exceed two doses nor 2,400 mg in 24 hours

Immediate-release or Extended-release Tablets

Smoking cessation and maintaining health are a must.

Caffeine should be avoided or limited to use as it might lead to the risk of nausea, palpitations, nervousness, rapid heartbeat, etc.

Alcohol intake should be avoided in patients, especially those with an underlying liver disorder or liver dysfunction.

The dietary restrictions should be individualized as per the patient's requirements.

Guaifenesin may be contraindicated under the following conditions:

• Hypersensitive to the ingredients of the medication

The physician should closely monitor the patients and keep pharmacovigilance as follows:

Carcinogenesis, Mutagenesis, Impairment of Fertility: Animal studies to assess the long-term carcinogenic and mutagenic potential or the effect on fertility in animals or humans have not been performed.

Avoid alcohol usage while on Guaifenesin medication, as alcohol can worsen the effects of any underlying disease condition, including conditions such as dizziness, blurred vision, etc.

Information related to the presence of Guaifenesin in breast milk has not been located. Products containing alcohol should be avoided.Some dosage formulations consisting of Guafenesin contain alcohol as one of the ingredients hence it is advised that such brands should be avoided.

Pregnancy Category C

When treatment for the cough is needed during pregnancy, Guaifenesin is found to be at standard OTC doses, is generally considered acceptable. Some sources also recommend use be reserved for significant maternal needs; products containing alcohol should be avoided.

No sufficient scientific evidence is traceable regarding the use and safety of Guaifenesin in concurrent use with any particular food.

The adverse reactions related to Guaifenesin can be categorized as follows:

Less Common

• Vomiting
• Stomach Cramps
• Drowsiness
• Inducing Of A Relaxed Easy State
• Excessive Sweating
• Nausea
• Difficulty Sleeping
• Constipation
• Headache

Rare

• Trouble Breathing
• Abnormal Nervous System Function Affecting Alertness
• Orthostatic Hypotension
• Low Blood Pressure
• Coughing up blood
• Atelectasis
• Decreased Lung Function
• Black, bloody, or tarry stools

The clinically relevant drug interactions of Guaifenesin are briefly summarized here:

Some dosage formulations consisting of Guafenesin contain alcohol/ethanol as one of the ingredients hence it is advised that such brands should be avoided.

• Disulfiram: May enhance the adverse/toxic effect of Products Containing Ethanol. Management: Do not use disulfiram with dosage forms that contain ethanol. Risk X: Avoid combination

• Methotrimeprazine: Products Containing Ethanol may enhance the adverse/toxic effect of Methotrimeprazine. Specifically, CNS depressant effects may be increased. Management: Avoid products containing alcohol in patients treated with methotrimeprazine. Risk X: Avoid combination

• Ornidazole: May enhance the adverse/toxic effect of Products Containing Ethanol. Specifically, a disulfiram-like reaction may occur. Risk X: Avoid combination

• Secnidazole: Products Containing Ethanol may enhance the adverse/toxic effect of Secnidazole. Risk X: Avoid combination.

The common side effects of Guaifenesin include the following:

• Hives
• Diarrhea
• Dizziness
• Stomach pain
• Headache
• Nausea or vomiting
• Skin rash

Pregnancy

Pregnancy Category C

When treatment for the cough is needed during pregnancy, Guaifenesin is found to be at standard OTC doses, and is generally considered acceptable. Some sources also recommend use be reserved for significant maternal needs. Some dosage formulations consisting of Guafenesin contain alcohol as one of the ingredients hence it is advised that such brands should be avoided.

Nursing Mothers

Information related to the presence of Guaifenesin in breast milk has not been located. Some dosage formulations consisting of Guafenesin contain alcohol as one of the ingredients hence it is advised that such brands should be avoided.

Pediatric Use

Safety and effectiveness for the use of cough and cold products in infants as well as young children are limited. Hence,the FDA does not recommend OTC use in infants or children <2 years of age as there is a risk of serious and life-threatening adverse effects including death .It is recommended to use with caution in pediatric patients ≥2 years of age.

Geriatric Use

There is no specific information available comparing the use of Guaifenesin Potassium in the elderly with use in other age groups.

Physicians should be knowledgeable and vigilant about the treatment pertaining to the treatment and identification of over dosage of Guaifenesin.

Overdose with Guaifenesin is unlikely to produce toxic effects since its toxicity is low. Very large doses may cause nausea and vomiting.

Pharmacodynamics

Guaifenesin has been categorized as an expectorant which acts by enhancing the output of phlegm or sputum and bronchial secretions by decreasing the adhesiveness and surface tension of such material. Furthermore, Guaifenesin is said to elicit an increased flow of less viscous gastric secretions that promotes ciliary action (all actions that ultimately change dry, unproductive coughing to coughs that are more productive and less frequent ). Essentially, by decreasing the viscosity as well as the adhesiveness of such secretions, Guaifenesin isa sid to enhance the efficacy of mucociliary activity in removing the accumulated secretions from the upper and lower airway.

Pharmacokinetics

• Absorption

Studies have shown that Guaifenesin is found to be well absorbed from and along the gastrointestinal tract after oral administration.

• Volume of distribution

The geometric mean apparent volume of distribution of the drug Guaifenesin is determined in healthy adult subjects and is found to be 116L (CV=45.7%).

• Metabolism

Following the oral administration of 400 mg guaifenesin, the agent experiences a rapid hydrolysis which is more than 60% of Guaifenesin hydrolyzed over a range of seven hours, with β-(2-methoxyphenyl)-lactic acid is found as the major urinary metabolite although no parent drug had been detectable in the urine. Moreover, it has been observed that Guaifenesin also experiences both oxidation as well as demethylation. In particular, the medication is said to be quickly metabolized hepatically by way of oxidation to β-(2-methoxyphenyl)-lactic acid .

• Route of elimination

After administration, Guaifenesin is found to be metabolized and then largely excreted in the urine.

1. https://go.drugbank.com/drugs/DB00874
2. https://www.wellrx.com/GUAIFENESIN DAC/lifestyle-interactions/
3. https://www.webmd.com/drugs/2/drug-999/guaifenesin-dac-oral/details/list-sideeffects
4. https://www.mayoclinic.org/drugs-supplements/guaifenesin-oral-route/side-effects/drg-20068720
5. https://www.pdr.net/drug-summary/Mucinex-guaifenesin-1275
6. https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=78987a51-82f7-4ca6-80ad-fa22d1f3e11a
7. https://www.drugs.com/pro/guaifenesin-nr.html#s-42232-9
8. https://medlineplus.gov/druginfo/meds/a682494.html