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Usual Adult Dose for: Cough Usual Pediatric Dose for: Cough Additional dosage information: Print this page Add to My Med List. Perrigo Company Aurobindo Pharma Limited. Moderate Sympathomimetics can antagonize the antihypertensive effects of vasodilators when administered concomitantly. Patients should be monitored to confirm that the desired antihypertensive effect is achieved. Severe The intravascular injection of a contrast medium should never be made following the administration of vasopressors since they strongly potentiate neurologic effects.
Serious neurologic sequelae, including permanent paralysis, have been reported following cerebral arteriography, selective spinal arteriography and arteriography of vessels supplying the spinal cord. Moderate Concomitant use of isavuconazonium with dextromethorphan may result in increased serum concentrations of dextromethorphan. Dextromethorphan is a substrate of the hepatic isoenzyme CYP3A4; isavuconazole, the active moiety of isavuconazonium, is a moderate inhibitor of this enzyme.
Caution and close monitoring are advised if these drugs are used together. Severe Dextromethorphan should be used cautiously, if at all, in patients receiving MAOIs; dextromethorphan is usually contraindicated in patients receiving traditional non-selective inhibitors of MAO e. Dextromethorphan can block neuronal uptake of serotonin and may produce excessive concentrations of serotonin in the CNS if combined with monoamine oxidase inhibitors MAOIs , with the potential for severe reactions.
The interaction may cause symptoms similar to those seen with meperidine and MAOIs. A single case report is noted of an acute, fatal drug reaction immediately following the ingestion of a cough mixture containing dextromethorphan in a patient who had been taking phenelzine; the year old female felt nauseated and dizzy, then collapsed. Her temperature rose to 42 degrees C and 4 hours later she died of a cardiac arrest. Similar cases of interactions between phenelzine or isocarboxazid and dextromethorphan have been reported in the medical literature.
There has also been a report of an interaction in which drowsiness and bizarre behavior appeared following the ingestion of a dextromethorphan lozenge with phenelzine. Selective inhibitors of MAO-B e. Severe In general, all types of sympathomimetics and psychostimulants should be avoided in patients receiving MAOIs due to an increased risk of hypertensive crisis. This applies to sympathomimetics including stimulants for ADHD, narcolepsy or weight loss, nasal, oral, and ophthalmic decongestants and cold products, and even respiratory sympathomimetics e.
Some local anesthetics also contain a sympathomimetic e. In general, medicines containing sympathomimetic agents should not be used concurrently with MAOIs or within 14 days before or after their use. Minor Use caution when administering ivacaftor and dextromethorphan concurrently. Co-administration of ivacaftor with CYP3A substrates, such as dextromethorphan, can theoretically increase dextromethorphan exposure leading to increased or prolonged therapeutic effects and adverse events; however, the clinical impact of this has not yet been determined.
Major Because of the potential risk and severity of serotonin syndrome, caution should be observed when administering levomilnacipran with other drugs that have serotonergic properties such as dextromethorphan. If serotonin syndrome is suspected, levomilnacipran and concurrent serotonergic agents should be discontinued. Moderate Sympathomimetic amines should be used with caution in patients with thyrotoxicosis since these patients are unusually responsive to sympathomimetic amines.
Based on the cardiovascular stimulatory effects of sympathomimetic drugs, the concomitant use of sympathomimetics and thyroid hormones can enhance the effects on the cardiovascular system. Patients with coronary artery disease have an increased risk of coronary insufficiency from either agent. Concomitant use of these agents may increase this risk further. The reduction in TSH secretion is not sustained; hypothyroidism does not occur.
Major Dextromethorphan should be used cautiously in patients receiving linezolid. Linezolid is an antibiotic that is also a reversible, non-selective MAO inhibitor. Dextromethorphan can block neuronal uptake of serotonin; excessive concentrations of serotonin in the CNS may result if dextromethorphan is combined with some non-selective MAO inhibitors. The potential for drug interaction was studied in healthy volunteers who were administered dextromethorphan i. A 'serotonin syndrome' was not noted.
However, this study involved limited co-exposure of the drugs in patients who were not acutely ill. Serious CNS reactions, such as serotonin syndrome, have been reported during the concurrent use of linezolid and psychiatric medications that enhance central serotonergic activity; therefore, caution is warranted with concomitant use of other agents with serotonergic activity, including dextromethorphan.
Major Linezolid may enhance the hypertensive effect of phenylephrine. Initial doses of phenylephrine, if given by intravenous infusion, should be reduced and subsequent dosing titrated to desired response. Closely monitor blood pressure during coadministration. Linezolid is an antibiotic that is also a weak, reversible nonselective inhibitor of monoamine oxidase MAO. Therefore, linezolid has the potential for interaction with adrenergic agents, such as phenylephrine.
Major Based on the mechanism of action of lorcaserin and the theoretical potential for serotonin syndrome, use with extreme caution in combination with other drugs that may affect the serotonergic neurotransmitter systems, including, dextromethorphan. In addition, lorcaserin inhibits CYP2D6-mediated metabolism of dextromethorphan. Increased exposure to dextromethorphan may result in additional adverse effects consistent with the serotonin syndrome including: Because manufacturers are constantly revising the ingredients of cough and cold formulas on the market, the patient should carefully assess product labels for the presence of dextromethorphan as an ingredient prior to any such product use.
Moderate Patients taking loxapine can have reduced pressor response to phenylephrine. Patients should be monitored for reduced efficacy if taking macitentan with a sympathomimetic. Major Caution and close observation should also be used when metaproterenol is used concurrently with other adrenergic sympathomimetics, administered by any route, to avoid potential for increased cardiovascular effects.
Major Methylphenidate can potentiate the actions of both exogenous such as dopamine and epinephrine and endogenous such as norepinephrine vasopressors. It is advisable to monitor cardiac function if these medications are coadministered. Vasopressors include medications such as epinephrine, dopamine, midodrine, and non-prescription medications such as pseudoephedrine and phenylephrine. Major Midodrine stimulates alpha-adrenergic receptors. Coadministration of midodrine with other vasoconstrictive agents, such as phenylephrine, may enhance or potentiate the effects of midodrine.
Major Because of the potential risk and severity of serotonin syndrome, caution should be observed when administering milnacipran or Levomilnacipran with other drugs that have serotonergic properties such as dextromethorphan. If serotonin syndrome is suspected, milnacipran and concurrent serotonergic agents should be discontinued. Exposure of drugs metabolized by CYP2D6 isoenzymes such as dextromethorphan may be increased when co-administered with mirabegron.
Dextromethorphan is primarily metabolized by CYP2D6. Therefore, appropriate monitoring and dose adjustment may be necessary. Moderate Although unlikely to occur with use of mirtazapine alone, there have been rare case reports of serotonin syndrome with the drug. It is likely that the activation of 5-HT 1A receptors by mirtazapine, combined with coadministration of other medications that potentiate the actions of serotonin, could result in serotonin syndrome.
Moderate Use caution if mitotane and dextromethorphan are used concomitantly, and monitor for decreased efficacy of dextromethorphan and a possible change in dosage requirements. Mitotane is a strong CYP3A4 inducer and dextromethorphan is a CYP3A4 substrate; coadministration may result in decreased plasma concentrations of dextromethorphan. Moderate Concurrent use of nabilone with sympathomimetics e. In a study of 7 adult males, combinations of cocaine IV and smoked marijuana 1 g marijuana cigarette, 0 to 2.
Moderate If use of a topical nasal decongestants e. Moderate Medications that augment release, decrease the metabolism of, or decrease the reuptake of serotonin, such as dextromethorphan, may interact with nefazodone by causing serotonin-related side effects, including serotonin syndrome. Whenever possible, these drug combinations should be avoided.
If serotonin-syndrome is suspected, offending agents should be discontinued. Minor Vasoconstricting nasal decongestants such as oxymetazoline, phenylephrine, pseudoephedrine, and tetrahydrozoline prolong the time to peak effect of nasally administered nicotine i. Administering these drugs together may result in increased dextromethorphan levels. A dextromethorphan dose reduction may be necessary if these drugs are used together.
Major Concomitant use of nitrates with sympathomimetics can result in antagonism of the antianginal effects of nitrates. In addition, amyl nitrite can block the alpha-adrenergic effects of epinephrine, possibly precipitating tachycardia and severe hypotension. Major Radiopaque contrast agents should not be injected arterially following the administration of vasopressors as they strongly potentiate the neurologic effects of contrast media such as paralysis.
The efficacy of dextromethorphan may be reduced if these drugs are administered concurrently. Major The administration of prophylactic vasopressors with oxytocin can cause severe, persistent hypertension, as the 2 drugs may have a synergistic and additive vasoconstrictive effect. This interaction was noted when oxytocin was given 3 to 4 hours after prophylactic vasoconstrictor in conjunction with caudal anesthesia.
The incidence of such an interaction may be decreased if vasopressors are not administered prior to oxytocin. Major The co-administration of panobinostat and dexchlorpheniramine; dextromethorphan; phenylephrine; pyrilamine and dexchlorpheniramine; dextromethorphan; pseudoephedrine is not recommended is not recommended; levels of dextromethorphan may increase.
If concomitant use cannot be avoided, closely monitor for signs and symptoms of dextromethorphan toxicity. Major Because of the potential risk and severity of serotonin syndrome, caution should be observed when coadministering drugs that have serotonergic properties such as dextromethorphan and paroxetine. In addition, paroxetine is a potent CYP2D6 inhibitor and may interfere with dextromethorphan metabolism, potentially leading to serotonin syndrome.
Minor Monitor for adverse effects associated with increased exposure to dextromethorphan if peginterferon alfa-2b is coadministered. Major Phendimetrazine is a phenylalkaline sympathomimetic agent. All sympathomimetics and psychostimulants, including other anorexiants, should be used cautiously or avoided in patients receiving phendimetrazine. The combined use of these agents may have the potential for additive side effects, such as hypertensive crisis or cardiac arrhythmia.
Moderate Other non-cardiovascular drugs with alpha-blocking activity such as phenothiazines, directly counteract the effects of phenylephrine and can counter the desired pharmacologic effect. Major Because phentermine is a sympathomimetic and anorexic agent i. The combined use of these agents may have the potential for additive side effects, such as hypertensive crisis or cardiac arrhythmias. Moderate Caution and close observation should also be used when pirbuterol is used concurrently with other adrenergic sympathomimetics, administered by any route, to avoid potential for increased cardiovascular effects.
Major Posaconazole and dextromethorphan should be coadministered with caution due to an increased potential for dextromethorphan-related adverse events. Posaconazole is a potent inhibitor of CYP3A4, an isoenzyme partially responsible for the metabolism of dextromethorphan. These drugs used in combination may result in elevated dextromethorphan plasma concentrations, causing an increased risk for dextromethorphan-related adverse events.
Major Because procarbazine exhibits some monoamine oxidase inhibitory MAOI activity, sympathomimetic drugs should be avoided. As with MAOIs, the use of a sympathomimetic drug with procarbazine may precipitate hypertensive crisis or other serious side effects. In the presence of MAOIs, drugs that cause release of norepinephrine induce severe cardiovascular and cerebrovascular responses. In general, do not use a sympathomimetic drug unless clinically necessary e.
If use is necessary within 2 weeks of the MAOI drug, in general the initial dose of the sympathomimetic agent must be greatly reduced. Patients should be counseled to avoid non-prescription OTC decongestants and other drug products, weight loss products, and energy supplements that contain sympathomimetic agents. Major Dextromethorphan should be used cautiously, if at all, in patients receiving drugs with MAOI like activity, such as procarbazine.
Dextromethorphan can block neuronal uptake of serotonin and may produce excessive concentrations of serotonin in the CNS if combined with procarbazine, with the potential for severe reactions. Therefore, propafenone may theoretically increase concentrations of other drugs metabolized by the CYP2D6 isoenzyme, including dextromethorphan. Moderate Initially, vasopressors may reduce propofol serum concentrations due to increased metabolic clearance secondary to increased hepatic blood flow.
An increase in the propofol dose may be required. Additionally, the vasopressor dose may need to be increased over time due to tachyphylaxis. Thus, these drugs may drive each other in a progressively myocardial depressive loop, which could lead to cardiac arrhythmias or cardiac failure. Minor Quinine inhibits CYP2D6 and may theoretically increase concentrations of other drugs metabolized by this enzyme, including dextromethorphan.
Major Racepinephrine is a sympathomimetic drug with agonist actions at both the alpha and beta receptors. Patients using racepinephrine inhalation are advised to avoid other non-prescription products containing sympathomimetics since additive adverse effects on the cardiovascular and nervous system are possible, some which may be undesirable. Side effects such as nausea, tremor, nervousness, difficulty with sleep, and increased heart rate or blood pressure may be additive. Patients should avoid use of non-prescription decongestants, such as phenylephrine and pseudoephedrine, while using racepinephrine inhalations.
Patients should avoid dietary supplements containing ingredients that are reported or claimed to have a stimulant or weight-loss effect, such as ephedrine and ephedra, Ma huang, and phenylpropanolamine. Severe The concomitant use of rasagiline and dextromethorphan is contraindicated. Isolated reports suggest dextromethorphan may produce a severe, adrenergic response and episodes of psychosis or bizarre behavior if administered to patients receiving MAOIs. The concomitant use of rasagiline and dextromethorphan was not allowed in clinical studies; therefore, the outcome of this potential interaction are unknown.
Moderate The concomitant use of rasagiline and sympathomimetics was not allowed in clinical studies; therefore, caution is advised during concurrent use of rasagiline and sympathomimetics including stimulants for ADHD and weight loss, non-prescription nasal, oral, and ophthalmic decongestants, and weight loss dietary supplements containing Ephedra. Although sympathomimetics are contraindicated for use with other non-selective monoamine oxidase inhibitors MAOIs , hypertensive reactions generally are not expected to occur during concurrent use with rasagiline because of the selective monoamine oxidase-B MAO-B inhibition of rasagiline at manufacturer recommended doses.
One case of elevated blood pressure has been reported in a patient during concurrent use of the recommended dose of rasagiline and ophthalmic tetrahydrozoline. One case of hypertensive crisis has been reported in a patient taking the recommended dose of another MAO-B inhibitor, selegiline, in combination with ephedrine. It should be noted that the MAO-B selectivity of rasagiline decreases in a dose-related manner as increases are made above the recommended daily dose and interactions with sympathomimetics may be more likely to occur at these higher doses.
Major The cardiovascular effects of sympathomimetics, such as phenylephrine, may reduce the antihypertensive effects produced by reserpine. Moderate Use caution if coadministration of ribociclib with dextromethorphan is necessary, as the systemic exposure of dextromethorphan may be increased resulting in increase in treatment-related adverse reactions. Patients should be monitored for reduced efficacy if taking riociguat with a sympathomimetic. Major Monitor for dextromethorphan-related adverse effects and toxicities if coadministered with rolapitant.
Dextromethorphan is a CYP2D6 substrate where an increase in exposure may significantly increase adverse effects, and rolapitant is a moderate CYP2D6 inhibitor; the inhibitory effect of rolapitant is expected to persist beyond 28 days for an unknown duration. Exposure to dextromethorphan following a single dose of rolapitant increased about 3-fold on Days 8 and Day Severe Monoamine oxidase inhibitors MAOIs , such as safinamide, are contraindicated for use with dextromethorphan.
The combination of MAOIs and dextromethorphan has been reported to cause episodes of psychosis and bizarre behavior. Moderate Severe hypertensive reactions, including hypertensive crisis, have been reported in patients taking monoamine oxidase inhibitors MAOIs , such as safinamide, and sympathomimetic medications, such as phenylephrine. If concomitant use of safinamide and phenylephrine is necessary, monitor for hypertension and hypertensive crisis. Patients should be monitored for reduced efficacy if taking selexipag with a sympathomimetic.
Moderate Dextromethorphan inhibits serotonin reuptake and therefore should be used cautiously with serotonin-receptor agonists as serotonin syndrome may result. Serotonin syndrome can be serious and consists of symptoms such as mental status changes, diaphoresis, tremor, myoclonus, hyperreflexia, and fever. Patients receiving serotonergic drugs in combination should be informed of the signs and symptoms of serotonin syndrome.
Major Because of the potential risk and severity of serotonin syndrome, caution should be observed when coadministering drugs that have serotonergic properties such as dextromethorphan and sertraline. Major Coadministration of sibutramine and dextromethorphan is not recommended by the manufacturer of sibutramine due to the potential for additive serotonergic activity. No clinical drug interactions have been reported for sibutramine and dextromethorphan. Major Concurrent use of sibutramine with other serotonergic agents may increase the potential for serotonin syndrome or neuroleptic malignant syndrome-like reactions.
Serotonin syndrome, in its most severe form, can resemble neuroleptic malignant syndrome. Monitor patients for adverse effects of dextromethorphan, such as dizziness and drowsiness. John's Wort, Hypericum perforatum: John's wort may have MAOI-like activities, and could potentially increase the cardiac stimulation and vasopressor effects of the sympathomimetics. John's wort should be used cautiously with any sympathomimetic agent. Moderate Due to possible additive effects on serotonin concentrations, it is advisable to avoid combinations of St.
John's wort with SSRIs. This interaction can lead to a reaction known as 'serotonin syndrome'. The syndrome may include symptoms of confusion, nausea, sweating, agitation, or more severe symptoms, like hypertension and unresponsiveness. Minor Caution is warranted with the concurrent use of tedizolid and dextromethorphan. Tedizolid is an antibiotic that is also a weak reversible, non-selective inhibitor of MAO.
Moderate Close clinical monitoring is advised when administering dextromethorphan with telaprevir due to an increased potential for dextromethorphan-related adverse events. If dextromethorphan dose adjustments are made, re-adjust the dose upon completion of telaprevir treatment. Dextromethorphan is partially metabolized by the hepatic isoenzyme CYP3A4; telaprevir inhibits this isoenzyme. Minor Concentrations of dextromethorphan may be increased with concomitant use of telithromycin.
Patients should be monitored for increased side effects. Moderate Use caution if coadministration of telotristat ethyl and dextromethorphan is necessary, as the systemic exposure of dextromethorphan may be decreased resulting in reduced efficacy. If these drugs are used together, monitor patients for suboptimal efficacy of dextromethorphan; consider increasing the dose of dextromethorphan if necessary.
Minor Terbinafine has been shown to inhibit hepatic CYP2D6 enzymes and thus, dextromethorphan metabolism. Major Concomitant use of sympathomimetics with beta-agonists might result in additive cardiovascular effects such as increased blood pressure and heart rate. Moderate Concurrent administration of theophylline or aminophylline with some sympathomimetics can produce excessive stimulation and effects such as nervousness, irritability, or insomnia.
Seizures or cardiac arrhythmias are also possible. Moderate The alpha-adrenergic effects of epinephrine can be blocked during concurrent administration of thiothixene. This blockade can cause an apparently paradoxical condition called epinephrine reversal, which can lead to severe hypotension, tachycardia, and, potentially, myocardial infarction. Patients taking thiothixene can have reduced pressor response to phenylephrine.
The formation of CYP enzymes may be suppressed by increased concentrations of cytokines such as IL-6 during chronic inflammation. Thus, it is expected that the formation of CYP enzymes could be normalized during tocilizumab receipt. For example, before tocilizumab receipt by patients with rheumatoid arthritis, the exposure of dextromethorphan, a CYP2D6 and CYP3A4 substrate, was comparable to exposure data from healthy subjects, but exposure to its metabolite dextrorphan, a CYP3A4 substrate was a fraction of that observed in healthy subjects.
The effect of tocilizumab on CYP enzyme activity may persist for several weeks after stopping tocilizumab. Utilize caution when using tocilizumab in combination with CYP3A4 substrate drugs where a decrease in effectiveness is undesirable. Major Sympathomimetics can antagonize the vasodilatory effects of antihypertensive agents when administered concomitantly. Major Because of the potential risk and severity of serotonin syndrome, caution should be observed when administering tricyclic antidepressants with other drugs that have serotonergic properties such as dextromethorphan.
Both trimipramine and dextromethorphan inhibit central serotonin reuptake. If serotonin syndrome is suspected, tricyclic antidepressants and concurrent serotonergic agents should be discontinued. Major Tricyclic antidepressants TCAs may markedly enhance the pressor response to parenteral direct-acting sympathomimetic agents such as norepinephrine and, to a lesser extent, epinephrine and phenylephrine. TCAs inhibit norepinephrine reuptake in adrenergic neurons, resulting in increased stimulation of adrenergic receptors.
Clinically, the patient might experience hypertension, headache, tremor, palpitations, chest pain, or irregular heartbeat. Major Sympathomimetics can antagonize the antihypertensive effects of vasodilators when administered concomitantly. Also, vasodilators can antagonize pressor responses to epinephrine. The manufacturer of vemurafenib suggests that concomitant use with agents with narrow therapeutic windows that are metabolized by CYP2D6 is not recommended.
If coadministration cannot be avoided, the manufacturer recommends considering a dose reduction of the concomitant drug. Major Because of the potential risk and severity of serotonin syndrome, caution should be observed when administering venlafaxine with other drugs that have serotonergic properties such as dextromethorphan. Dextromethorphan should be used in lower doses in patients receiving serotonin-potentiating medications, such as venlafaxine, which are inhibitors of CYP2D6, the isoenzyme responsible for metabolism of dextromethorphan.
If serotonin syndrome is suspected, venlafaxine and concurrent serotonergic agents should be discontinued. Major Because of the potential risk and severity of serotonin syndrome, caution should be observed when administering vilazodone with other drugs that have serotonergic properties such as dextromethorphan. Patients receiving vilazodone and dextromethorphan should be monitored for the emergence of serotonin syndrome, particularly during treatment initiation and during dosage increases.
Vilazodone and dextromethorphan should be discontinued if serotonin syndrome occurs and supportive symptomatic treatment should be initiated. Major Because of the potential risk and severity of serotonin syndrome, caution should be observed when administering vortioxetine with other drugs that have serotonergic properties such as dextromethorphan. Patients receiving dextromethorphan in combination with vortioxetine should be monitored for the emergence of serotonin syndrome or other adverse effects.
If serotonin syndrome is suspected, vortioxetine and concurrent serotonergic agents should be discontinued. Major At high doses, yohimbine may nonselectively inhibit MAO and also, at normal doses, activates the sympathetic nervous system. Traditional MAOIs can cause serious adverse effects when taken concomitantly with sympathomimetics. It is the d-isomer of levorphanol but has none of the analgesic, respiratory depressive, or sedative effects associated with opiate agonists.
Dextromethorphan has similar antitussive effects as codeine. Dextromethorphan acts on the cough center in the medulla to raise the threshold for coughing by decreasing the excitability of the cough center. Naloxone, an opiate-antagonist, does not block the antitussive effects of dextromethorphan. Guaifenesin is an expectorant which increases the output of phlegm sputum and bronchial secretions by reducing mucous adhesiveness and surface tension.
The increased flow of less viscous secretions promotes ciliary action and changes a dry, unproductive cough to one that is more productive and less frequent. By reducing the viscosity and adhesiveness of secretions, guaifenesin increases the efficacy of the mucociliary mechanism in removing accumulated secretions from the upper and lower airway. The expectorant effect can reduce cough frequency.
Guaifenesin can also be beneficial for irritating, nonproductive coughs and for conditions in which thick mucous secretions are produced. Phenylephrine possesses both direct and indirect sympathomimetic effects, primarily as a postsynaptic alpha-adrenergic agonist, producing potent vasoconstriction. An indirect effect due to the release of norepinephrine plays a small role in the overall action of phenylephrine.
Phenylephrine does not stimulate beta2-adrenergic receptors in the bronchi or peripheral blood vessels or beta1-adrenergic receptors of the heart. Phenylephrine increases resistance and, to a lesser extent, decreases capacitance of blood vessels. Following oral administration, constriction of blood vessels leads to reduced blood flow to the nose, decreased amount of blood in the sinusoid vessels, and decreased mucosal edema, which relieves nasal congestion.
Dextromethorphan, guaifenesin, and phenylephrine combinations are given orally. Dextromethorphan is administered orally. Dextromethorphan undergoes rapid and extensive hepatic metabolism to demethylated metabolites including the active metabolite, dextrorphan. Dextromethorphan is primarily metabolized by CYP2D6 isoenzymes. The rate of metabolism varies between individuals according to phenotype extensive or poor metabolizers.
The plasma half-life is normally about 11 hours, and antitussive activity can last for 5—6 hours. Excretion is primarily by renal elimination of metabolites; some drug is excreted unchanged. No unchanged drug could be detected in the urine following administration of oral guaifenesin. Additional pharmacokinetic information is not known. Phenylephrine is metabolized in the liver and intestine by monoamine oxidase. The metabolites and their route and rate of excretion have not been fully identified.
The pharmacologic effect of phenylephrine is terminated at least in part by uptake of the drug into tissues. Dextromethorphan is rapidly absorbed from the GI tract, with antitussive activity appearing within 15—30 minutes. Following oral administration, guaifenesin is rapidly absorbed from the GI tract. Phenylephrine is irregularly absorbed from and readily metabolized in the GI tract.
Following oral administration of phenylephrine as a single agent, nasal decongestion occurs within 15—20 minutes and persists for up to 4 hours. Your Name Your name is required. Recipient's Email Separate multiple email address with a comma Please enter valid email address Recipient's email is required. Your email has been sent. Related Drug Information Drug Summary. Oral dosage non-prescription OTC immediate-release products, including various concentrations of oral solutions, drops, and syrups.
Children and Adolescents 12 years and older. Children 6 to 11 years. Oral dosage prescription-only, immediate-release capsules containing dextromethorphan 14 mg, guaifenesin mg, phenylephrine 7mg per capsule, e. Adults, Adolescents, and Children 12 years and older. Oral dosage prescription-only, extended-release tablets containing dextromethorphan 60 mg; guaifenesin mg; phenylephrine 40 mg per tablet; e.
Oral dosage extended-release tablets containing dextromethorphan 25 mg, guaifenesin mg, phenylephrine 20 mg per tablet; e. Do not exceed recommended dosage limits for the specific product prescribed; the following are general guidelines: Angina, cardiac arrhythmias, cardiac disease, cardiomyopathy, cerebrovascular disease, coronary artery disease, diabetes mellitus, hypertension, hyperthyroidism, peripheral vascular disease. Bladder obstruction, prostatic hypertrophy, urinary retention.