Virtussin AC – Ingredients, uses, dosage and side effects

What is Virtussin AC?

Virtussin AC is a brand name for a preparation which is used as a cough suppressant and expectorant containing the generic drugs codeine and guaifenesin.

It mainly helps to stop or decrease the coughing which occurs due to inhaled allergens and in some cases common cold. However, this product will not treat an infection.

Due to the presence of codeine, this preparation is considered narcotic. This is an over the counter product which is still under consideration for its safety and efficacy by the Food and Drug Administration (FDA).

Ingredients of Virtussin AC

Active ingredients: every 5ml of this syrup contains guaifenesin USP – 100 mg and codeine phosphate 10 mg in about 3.5% alcohol v/v.

Excipients: in addition to the active ingredients, this preparation contains artificial cherry flavor, caramel, citric acid, disodium edetate, glycerin, purified water, saccharin sodium, sodium benzoate, sorbitol solution and FD&C Red #40.

What are the indications for Virtussin AC?

  • Virtussin AC is recommended for providing relief and reducing the cough which occurs due to minor bronchial or throat irritation. This irritation is because of the inhaled allergens or a common cold.
  • It is also recommended to decrease and slacken the phlegm (mucus) and other bronchial secretions to produce a productive cough.

How does Virtussin AC exert its action?

This preparation contains a combination of two drugs and the cumulative effect of these two drugs has been clinically considered useful in helping with a cough and other associated symptoms.

Codeine is a narcotic drug which shows its anti-tussive action by acting directly on the receptors which are present in the cough center of the medulla in the brain.

Additional beneficial effects produced by codeine are that brings out a drying effect in the respiratory tract making the bronchial secretions more viscous.

A lower dose of codeine is sufficient for suppressing the cough as compared to that which is required for producing analgesia.

What are the side effects of Virtussin?

Guaifenesin is of the most commonly used expectorant medicine which helps to increase the production of sputum (phlegm) and other significant and insignificant bronchial secretions.

This is done by decreasing adhesiveness and surface tension on the bronchial lining. This increase in the passage of viscous secretions enhances the ciliary action and transforms an unproductive and dry cough to a more productive cough which occurs with less frequency.

When the viscosity and adhesiveness decreases, this drug increases the efficacy of the mucociliary action in getting rid of the accumulated secretions from both the upper and lower respiratory airway tract.

Guaifenesin’s expectorant effect decreases the cough frequency. It has also proven to be beneficial in reducing the irritation and nonproductive cough in those medical conditions where thick mucus secretions are formed.

Pharmacokinetics of Virtussin AC

This narcotic preparation is available in oral solid and liquid form and is administered orally. As it contains two active ingredients, both of these show different pharmacokinetic parameters.

Codeine is metabolized majorly by glucuronidation with a small quantity of drug metabolized to an active substance morphine through O-demethylation.

This is hepatically metabolized with the help of isozymes CYP2D6. However, both the parent drug codeine has a different elimination half then the active compound morphine.

The half-life for codeine is reported to vary from 3 to 5 hours and approximately 1 to 2 hours for morphine. It is observed that only negligible amounts of the parent drug or metabolized compound or both are excreted in feces.

Codeine has shown a good absorption once orally administered shows maximum anti-tussive effect within 1 to 2 hours after the ingestion of drug and lasts for 4 to 7 hours. Only minute protein binding has been reported.

Guaifenesin shows a completely different pharmacokinetic profile from codeine. This drug undergoes a quick metabolism reaction and a major portion of about 60% is rapidly hydrolyzed within 6 – 7 hours.

After being hydrolyzed, the drug is then eliminated from the body via urine. The main urinary metabolite is beta-(-2methoxyphenoxy)- lactic acid.

Excessively using guaifenesin may lead to urolithiasis that is the formation of renal stones. It has been reported to contain beta-(-2methoxyphenoxy)- lactic acid and other minor metabolites of guaifenesin.

This drug shows a fast absorption in the gastrointestinal tract and the elimination half-life of the drug is observed to be about 1 hour.

It was demonstrated that no unchanged drug was found in the urine after guaifenesin was orally administered. This drug is still being studied for further pharmacokinetic parameters.

What is the recommended dosage of Virtussin AC?

  • Virtussin AC is mainly used for the momentary relief of a non-productive cough which occurs due minor irritation in throat and bronchia which may be a symptom of a common cold, acute bronchitis or inhaled irritants. A number of formulations of Virtussin AC are being manufactured each containing different strengths of the two active ingredients.
  • The normal recommended dose in adults (using capsules which have 9 mg of codeine and 200 mg of guaifenesin) is 2 capsules PO administered to the patient 4 hourly or as the need requires. In a single day, not more than 12 capsules should be used.
  • The normal recommended dose in adults (using tablets which have 10 mg of codeine and 300 mg of guaifenesin) is 1 capsules PO administered to the patient 4 hourly or as the need requires. In a single day, not more than 6 tablets should be used.
  • The normal recommended dose in adults (using tablets which have 10 mg of codeine and 400 mg of guaifenesin) is 1 capsules PO administered to the patient 4 hourly or as the need requires. In a single day, not more than 6 tablets should be used.
  • The normal recommended dose in adults (using oral syrup) should be such that it has 20 mg of the active codeine PO given in a single day with a gap of 4 to 6 hours. In severe cases, the dose can be increased up to 200 mg/ day of codeine and 2400 mg/ day of guaifenesin.

Are there any dosing considerations for Virtussin AC?

No special recommendations are yet available for altering the normal doses in patients who are suffering from hepatic impairment.

On the basis of the condition and age of the patient, the dose can be modified to a lowest effective dosage at which the clinical response is obtained.

In patients who are renally impaired, should be given this medicine with great caution as codeine is eliminated from the body via urine. However, no special guidelines for dose adjustments of guaifenesin are available.

In patients who have a creatinine clearance (CrCl) is greater than 50 no changes are advised in the normal dose.

In patients have a decreased creatinine clearance (CrCl) in the range of 10 – 50ml/ min the codeine dose should be decreased by 25%. In patients, who are severely ill and have a creatinine clearance of below 10ml /minute the dose of codeine should be reduced by 50%.

Virtussin AC in pregnancy and breastfeeding

FDA has not recommended the use of products which have codeine in nursing mothers. This is because of the fact that serious unwanted effects can take place which includes severe sedation and drastic respiratory depression in the infants who are being fed. In the infants who ingested the milk from such mother, it is suggested to closely and regularly monitor for any signs of sedation or respiratory depression.

When the nursing mother stops taking opioid medicines or when breastfeeding is stopped, withdrawal symptoms are visible in infants. No data for the presence of guaifenesin in breast milk is available.

However, codeine and its metabolites are detected in variable amounts in the breast milk. No effect of codeine or morphine is seen on the production of milk.

Those females who have a normal metabolism system, codeine which is secreted in the breast milk is in low amounts and is dose-dependent.

Those who are genetically ultra-rapid metabolizers of codeine have adversely affected the infant and in some cases caused the death of the infant.

Virtussin AC abuse

As this preparation contains codeine which is a narcotic substance, it has a risk of causing psychological and physical dependence (that is drug addiction) or can cause a criminal diversion.

Being addicted to the drug is a chronic illness which is demonstrated by using any means to obtain the drug and feeling a compulsion to administer it even though the user has knowledge of all the possible adverse events.

Those who have a past medical history of drug addiction are more prone to the reversion when Virtussin AC is administered. It is important to know that psychological dependence is not always accompanied by tolerance.

Moreover, codeine abuse can also take place in the nonexistence of psychological dependence. This is typified by misusing the product for nonmedical purposes mostly combined with other CNS stimulants.  For this reason, Virtussin AC should be carefully prescribed.

Virtussin AC abrupt discontinuation

When Virtussin AC is prescribed at a lower dose or for short duration of time for its anti-tussive action, there is no need for the gradual decreasing of the dose at the time the therapy is about to finish.

When higher doses or administration is done for chronic periods, it is necessary to slowly taper the dose of Virtussin AC.

This is because of the abrupt discontinuation of this medicine, codeine is likely to bring out withdrawal symptoms to the user.

It is suggested depending upon the condition of the patient, a reduction in 50% of the dose every alternate day will decrease the chances of withdrawal symptoms to take place.

Can I take Virtussin AC with alcohol?

Alcohol may potentiate the central nervous system (CNS) depressant effects of opioid analgesic codiene if used together with Virtussin AC.

Concomitant use may result in additive CNS depression and impairment of judgment, thinking, and psychomotor skills. In more severe cases, hypotension, respiratory depression, profound sedation, coma, or even death may occur.

Can I take Virtussin AC with oxycodone?

Concomitant use of opioids with benzodiazepines or other central nervous system (CNS) depressants (e.g., nonbenzodiazepine sedatives/hypnotics, anxiolytics, muscle relaxants, general anesthetics, antipsychotics, other opioids, alcohol) may result in profound sedation, respiratory depression, coma, and death.

The risk of hypotension may also be increased with some CNS depressants (e.g., alcohol, benzodiazepines, phenothiazines).

Virtussin AC use in geriatric patients

Gradually with age, the normal body functions began to decline and elderly patients become more sensitive and are at a greater risk of suffering from adverse events.

On using CNS stimulants and CNS depressants due to the adverse effects, care is needed while prescribing it in geriatric patients. It should be started with the lowest possible effective dose.

Considerations should be made for any improper functioning in the cardiac, renal or hepatic systems or any simultaneous drug therapies or medical conditions.

Opioids have been considered as unsuitable drugs to be used in those elderly patients who had a past surgical history of fractures or joint replacements.

However, those who are only suffering from pain associated with any kind of bone disorder can be kept on exception as opioids are also being used for the purpose of pain management.

Coadministration of Virtussin AC in patients who are taking psychoactive substances can produce ataxia, syncope and additional falls in them. Approaches should be made in reducing the risk of falls in these patients.

Virtussin AC, when prescribed for common cold or bronchitis, should not be used for greater than 2 weeks unless and until no other alternative therapies are available.

Can I use Virtussin AC if I have hypothyroidism?

Patients with hypothyroidism may have increased risk of respiratory depression and prolonged CNS depression related to the use of Virtussin AC which contains narcotic (opioid) analgesic agents.

These substances may also enhance the effects of hypothyroidism including impaired mentation, lethargy, depression, and constipation.

Therapy with opioids should be used with caution and initiated at lowered dosages in patients with uncontrolled hypothyroidism or myxedema. Subsequent doses should be titrated based on individual response rather than a fixed dosing schedule.

Can I use Virtussin AC if I have arrhytmias?

Codeine of Virtussin AC may have cholinergic activity. Large doses and/or rapid intravenous administration may produce bradycardia and arrhythmia via stimulation of medullary vagal nuclei.

Unlike other agents in the class, meperidine also has anticholinergic activity and may cause either bradycardia or tachycardia.

Therapy with opiate agonists should be administered cautiously in patients with a history of arrhythmias. Clinical monitoring of cardiovascular status is recommended during therapy. Bradycardia and other cholinergic effects produced by these agents may be controlled with atropine.

Can Virtussin AC be used in patients with increased intracranial pressure?

The hypoventilation related to the use of  Virtussin AC containing opiate agonist such as codeine , may induce in some cases cerebral hypoxia and vasodilatation with an increase in intracranial pressure.

Unless mechanical ventilation is provided,  caution is advised when opiate agonists are given to patients with head injury, intracranial lesions, or a preexisting elevated CSF pressure.

Also, healthcare professionals treating such patients should be aware that opiate agonists may interfere with the evaluation of CNS function, especially with respect to consciousness levels, respiratory status, and pupillary changes.

Can Virtussin AC be used in patients with liver disease?

Narcotic (opioid) analgesic agents such as codeiene in the Virtussin AC product is extensively metabolized by the liver, The serum concentrations of this agent and its metabolites may be increased and the half-lives prolonged in patients with impaired hepatic function.

Therapy with opioids should be administered cautiously and initiated at reduced dosages in patients with liver disease. Subsequent doses should be titrated based on individual response rather than a fixed dosing schedule.

Can Virtussin AC be used in patients with urinary retention?

Codeine of the Virtussin AC may inhibit the urinary voiding reflex and increase the tone of the vesical sphincter in the bladder.

Acute urinary retention requiring catheterization may occur, particularly in patients with prostatic hypertrophy or urethral stricture and in elderly patients.

These agents may also decrease urine production via direct effects on the kidney and central stimulation of the release of vasopressin.

Therapy with opioids should be administered cautiously in patients with or predisposed to urinary retention and/or oliguria. The effects on smooth muscle tone appear to be the most pronounced with morphine.

Can I use Virtussin AC with antidepressants?

Concurrent use of Virtussin A/C with TCAs such as amitriptyline increases the risk of developing side effects such as confusion, dizziness, drowsiness, and difficulty concentrating.

In the elderly, these side effects are more pronounced and can lead to impairment in thinking, judgment, and motor coordination.

Can I use Virtussin AC with CNS depressants?

All CNS depressants such as benzodiazepines, barbiturates, alcohol, opioids etc. can lead to respiratory distress, coma, and even death when used in concurrence with the drug.

What are the possible side effects of Virtussin AC?

The following side effects are seen with the use of the drug. Immediately go to your nearest ER if any of the following side effects are experienced by the user.

  • Allergy: signs can range from individual to individual and can range from as simple as itching to something more serious such as an anaphylactic shock
  • Dizziness which may lead to unconsciousness
  • Confusion
  • Hallucinations
  • Seizures
  • Excruciating headache
  • Mood swings
  • Abdominal pain
  • Difficulty in urination
  • Pain in chest
  • Tachycardia
  • Breathing anomalies: slow breathing, shallow breathing, noisy breathing
  • Myalgia
  • Constipation

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