Li Shu

Quick links to important sections

Li Shu

Medically reviewed

Marina Burgos

Last updated on 22/12/2025

This page provides general, reference-level information compiled from official medical sources. It is not a substitute for professional medical advice, diagnosis, or treatment. For decisions about your health, please consult a qualified healthcare professional.

Overview of Li Shu

Property Description
Active Ingredients Acetaminophen, Pseudoephedrine
Form Oral Tablet, Capsule, or Solution
Pharmacological Class Analgesic, Antipyretic, and Nasal Decongestant Combination
Primary Therapeutic Intent Symptomatic relief of common cold and flu discomforts
Origin Synthetic (Pharmaceutical compound)

Li Shu is a fixed-dose combination preparation classified as an upper respiratory combination product, specifically designed for the symptomatic relief of discomforts related to the common cold and flu. This medicine is a synthetic entity that delivers its effects through the systemic action of two distinct active ingredients administered via the oral route in forms such as an oral tablet, capsule, or oral solution. It is defined by its integrated pharmacological profile as an Analgesic, Antipyretic, and Nasal Decongestant Combination.

Classification and Active Composition

Li Shu combines the two active ingredients, Acetaminophen and Pseudoephedrine, to provide simultaneous relief from both pain and congestion. Acetaminophen is officially classified as an analgesic and antipyretic, functioning to modulate the body's pain threshold and reduce elevated fever. Acetaminophen functions in systemic pain and temperature management.

Conversely, Pseudoephedrine is a sympathomimetic agent that serves as the nasal decongestant, a class of medications that primarily causes the narrowing of blood vessels in the nasal passages. This composition is a recognized formulation for common cold symptom management, often available globally under similar formulations, demonstrating the widespread acceptance of this combination for general symptomatic relief.

Functional Role as a Combination Medicine

The primary therapeutic intent of Li Shu is to offer efficient, simultaneous symptomatic relief for the co-occurring acute discomforts of upper respiratory illness. The dual action allows the medication to mitigate minor aches and pains and reduce high temperature, while concurrently addressing the physical obstruction caused by sinus congestion and stuffy nose.

The dual action of these ingredients is intended for the simultaneous treatment of pain and congestion. This integrated approach focuses on relieving distress during the course of the cold or flu. Li Shu, typically presented in an oral tablet form, is targeted at patients seeking relief from the acute combination of headache and nasal blockage.

Regulatory References

  1. Acetaminophen: MedlinePlus Drug Information
  2. Pseudoephedrine: MedlinePlus Drug Information

What side effects are possible with Li Shu?

Possible Side Effects and Safety Information

This section describes the medicine's safety profile based strictly on official governmental regulatory documents.

Adverse Reaction Scope

The adverse reaction profile for Li Shu, a combination of acetaminophen and pseudoephedrine, is defined by effects across several System-Organ Classes (SOCs), including Nervous System, Psychiatric Disorders, Cardiovascular, and Gastrointestinal systems.

Common Adverse Reactions

Regulatory documents classify effects like insomnia, nervousness, headache, dizziness, dry mouth, and nausea as common adverse reactions.

Serious Adverse Reactions and Risks

The official labeling documents rare but serious risks, primarily linked to the individual active components. Serious reactions include severe liver damage or failure (associated with exceeding the maximum recommended daily dose of the acetaminophen component) and severe cutaneous reactions (e.g., SJS, TEN, AGEP). Risks linked to pseudoephedrine include cardiovascular events (e.g., high blood pressure, tachycardia, myocardial infarction) and cerebrovascular events (e.g., PRES/RCVS), which are generally classified as having a Frequency Not Known.

Population-Specific Safety Considerations

Official safety notes define constraints for specific patient groups. Individuals with severe hepatic impairment face an increased risk of liver toxicity. Special caution is noted for older adults, who may be more susceptible to central nervous system effects (dizziness, confusion) and cardiovascular side effects. Additionally, men with prostatic enlargement have an officially recognized increased risk of urinary retention.

Safety Restrictions and Limitations

The regulatory profile imposes strict constraints on the total daily intake of acetaminophen, and the medicine is strictly contraindicated for use in individuals who have taken a Monoamine Oxidase Inhibitor (MAOI) within the last 14 days due to the risk of severe hypertensive reaction. The risk of liver injury is also increased in conjunction with regular alcohol consumption.

Connection to the Overall Safety Profile

The official safety information structures the understanding of risks by emphasizing the dual concerns of hepatotoxicity from the dose-limited acetaminophen component and the cardiovascular/cerebrovascular risks associated with the pseudoephedrine component. This regulatory framework formally categorizes the spectrum of documented effects, from common expected reactions to rare but serious outcomes.

Overdose and Emergency Response

A suspected overdose of Li Shu requires immediate medical attention due to the distinct and serious risks posed by its two active components. Symptoms of overdose may initially include non-specific signs such as nausea, vomiting, diaphoresis, and malaise. However, the official overdose profile is defined by two severe and potentially life-threatening domains.

Overdose of the acetaminophen component carries a significant risk of Fatal hepatic necrosis and subsequent liver failure, indicated by later signs like elevated liver enzymes and jaundice. Prompt measurement of the plasma Acetaminophen concentration is critical to guide the timely administration of the specific antidote, N-acetylcysteine (NAC). Individuals with chronic alcoholism or pre-existing hepatic impairment face a heightened risk of this toxicity.

The pseudoephedrine component causes central nervous system and cardiovascular hyperstimulation. This can manifest as Tachycardia, severe Hypertension, Restlessness, and potentially lead to Seizures or Cardiovascular collapse. Management involves continuous monitoring of the patient's cardiac function and neurological status, along with symptomatic and supportive treatment, as no specific antidote is known for this component. Activated charcoal may be used for gastric decontamination in the early stages of ingestion.

Therapeutic Uses of Li Shu

What Li Shu Treats: Main Uses and Benefits

This medication is relevant in conditions characterized by acute or disruptive episodes, providing support during the symptomatic phases of the common cold and flu. It is commonly used to help with groups of symptoms that may appear suddenly, including minor aches and pains, elevated body temperature, and nasal congestion.

The primary therapeutic purpose is to provide simultaneous support for multiple symptoms, as this medicine is applied in contexts where additional symptomatic support is needed. This medicine is relevant when symptoms interfere with daily functioning and short-term supportive relief is appropriate. The aim is to offer symptomatic relief, which may assist with maintaining functional stability and supports general well-being during symptomatic periods. This is commonly used for the acute combination of nasal obstruction and headache.


Clinical Context: Managing Co-Occurring Symptoms This combination is used when systemic pain, fever, and congestion all occur together, contributing to improved comfort during periods of heightened symptoms.

Regulatory References

  1. European Medicines Agency guidance on Pseudoephedrine combinations

Eligibility and Restrictions for Use

The official regulatory documents define the population eligible to use the combination medicine Li Shu based on age restrictions and the presence of severe underlying health conditions. The medicine is approved for use in adults and adolescents 12 years of age and older. For the pediatric population, use is generally not recommended below this age threshold.

Contraindicated Populations (Must Not Use) Populations Requiring Caution/Restriction
Severe Hypertension or Severe Coronary Artery Disease. Mild-to-moderate hypertension or diabetes mellitus.
Severe Hepatic Impairment or Severe Active Liver Disease. Prostatic Hypertrophy or difficulty urinating.
Use of Monoamine Oxidase Inhibitors (MAOIs) within the last 14 days. Hyperthyroidism or certain cardiac arrhythmias.
Known Hypersensitivity to any active ingredient. Moderate Hepatic or Renal Impairment.

Li Shu is not recommended for use during pregnancy and is generally contraindicated while breastfeeding, as its active components can cross into breast milk or affect the fetus. Older adults are also advised to use the medicine with caution. These formal exclusions reflect regulatory constraints designed to mitigate cardiovascular and hepatic risks associated with the active ingredients.

What should I know about interactions with other medicines?

The official interaction profile for Li Shu, a fixed-dose combination, is structured by constraints relating to both its Acetaminophen and Pseudoephedrine components, requiring the avoidance of certain substances and drug classes to prevent severe outcomes.

Formally Prohibited Combinations

Co-administration is strictly contraindicated with certain drug classes. This includes Monoamine Oxidase Inhibitors (MAOIs), where a separation period of at least 14 days is mandated after stopping the MAOI, due to the severe pharmacodynamic risk of a hypertensive crisis. Use is also prohibited with any other medicine containing Acetaminophen (APAP) to prevent additive exposure and the risk of acute liver failure, a regulatory constraint to manage overdose risk. Other sympathomimetic agents (e.g., other decongestants) are also contraindicated to prevent severe additive cardiovascular effects.

Documented Exposure and Pharmacodynamic Interactions

  • Chronic Alcohol Consumption: The regulatory label documents a heightened risk of severe, potentially fatal, acetaminophen-induced liver damage in individuals who consume three or more alcoholic drinks per day (a pharmacokinetic interaction). This risk is compounded in cases of pre-existing hepatic impairment.
  • Cardiovascular Agents: Pseudoephedrine may antagonize the therapeutic effects of certain antihypertensive agents (including beta-blockers) via a pharmacodynamic interaction, potentially leading to a loss of blood pressure control.
  • Exposure Modification: Urinary alkalinizers (e.g., Acetazolamide) are documented to significantly increase the plasma levels and prolong the effect of Pseudoephedrine by altering its renal clearance (a pharmacokinetic interaction). Conversely, Cholestyramine requires a specific separation of administration to avoid reduced absorption of the Acetaminophen component.

Mechanism of Action

The analgesic component (Acetaminophen) acts primarily within the Central Nervous System ( CNS), where it is involved in the inhibition of Cyclooxygenase ( COX) enzyme activity, which reduces the synthesis of Prostaglandin E2 ( PGE2) in the hypothalamus. This molecular action modulates key physiological processes: it results in the resetting of the hypothalamic temperature set point and attenuates the transmission of nociceptive signals via descending pathways.

The decongestant component (Pseudoephedrine) engages the Peripheral Sympathetic Nervous System by acting as a sympathomimetic agent, directly activating alpha1-adrenergic receptors on vascular smooth muscle. This mechanism initiates a vasoconstriction cascade that reduces blood flow within the nasal and sinus mucosa. The resulting physiological consequence is the shrinkage of swollen tissues, leading to a reduction of blood volume that results in decreased nasal airway resistance.

The overall physiological effect of the combination is achieved through two distinct, non-overlapping mechanisms that are functionally additive. While one component modulates central pathways for temperature and pain control, the other targets peripheral vascular receptors for tissue swelling. This pattern enables the simultaneous modulation of two separate physiological processes that shape the drug's effect profile.

Dosage and Administration Information

How to Use Li Shu

Li Shu, an oral combination product containing Acetaminophen and Pseudoephedrine, is administered through the oral route exclusively. It is available in various forms, including tablets, capsules, and oral solution. The use of this medicine is structured around strict, intermittent dosing patterns, and it is intended for short-term applications.


Official Administration Guidelines

Parameter Instruction
Route of administration Oral use only.
Dosing schedule Adults and adolescents ge 12 years typically take the standard single unit dose. The total dose of the Acetaminophen component must not exceed 4000 mg in 24 hours.
Frequency pattern The medicine is taken as needed (PRN), with a required interval of 4 to 6 hours between doses.
Timing in relation to meals May be administered with or without food.
Preparation requirements Liquid forms must be measured using a calibrated milliliter device to ensure dosage accuracy.
Duration constraint Use should generally not exceed 7 consecutive days.

Procedural Context and Constraints

This medicine is not intended for chronic, long-term use, and its administration must strictly adhere to the dosing intervals to prevent surpassing the maximum daily limits. The instructions for adolescents aged 12 and older align with the standard adult dosing schedule. In the event a dose is missed, the user should maintain the minimum required interval of at least 4 hours before taking the next dose. Compliance with these administration guidelines ensures the proper use of the fixed-dose combination.

Recent Clinical Evidence

Research Evidence / Overview of Studies for Li Shu

Evidence for Symptomatic Relief of Cold and Flu Discomforts

The research into Li Shu, which combines two active ingredients (Acetaminophen and Pseudoephedrine), focuses on studies exploring acute, short-term changes in symptoms for conditions associated with acute or disruptive episodes, specifically the common cold and flu. The primary evidence base consists of randomized controlled trials (RCTs). These short-term studies were used in research exploring how symptoms change over time when the combination is taken versus a placebo or one of the active ingredients alone.

The main focus of this research was on outcomes related to physical discomfort, examining how symptoms like nasal congestion, headache, and body aches are measured in the context of the studies. These measurements relied heavily on patient-reported outcomes describing perceived discomfort, where participants rate their symptoms on various severity scales. Findings describe patterns observed in the studies that evaluate co-occurring symptoms, such as pain/fever and nasal congestion.

Follow-up Duration in Clinical Research

The follow-up durations used in the research are short-term and reflect the acute nature of the cold and flu. Research exploring short-term symptom changes typically focuses on the immediate period after taking the medication, often tracking outcomes for only a few hours or up to one day. Therefore, there is limited information for long-term outcomes or repeated use of this combination over an extended period, as these scenarios are not typically the focus of the available acute research.

Evidence in Specific Groups (Special Populations)

The research predominantly involves healthy adults, meaning the findings describe group patterns, not personal outcomes, and may not fully describe outcomes for all patient groups. Data for certain groups remain insufficient, particularly regarding outcomes for the combination in older adults and individuals with underlying chronic health conditions like high blood pressure, who were often excluded from the core RCTs.

Frequently Asked Questions (FAQ)

Common questions about Li Shu (FAQ)


Q: Is Li Shu the same kind of medication as [similar common drug name]?

Official product information states that Li Shu is a combination medicine belonging to two pharmacological classes: an Analgesic/ Antipyretic for pain and fever, and a Nasal Decongestant. The combined use of these two types of ingredients is intended for the simultaneous relief of multiple cold and flu symptoms.


Q: Are the side effects of Li Shu generally mild?

Regulatory documents define the safety profile by classifying adverse effects as either common (such as headache or nervousness) or serious but rare. Serious risks are primarily linked to misuse of the active ingredients, such as severe liver damage from the Acetaminophen component. Patients are advised to monitor for all documented effects, especially the serious warnings listed on the label.


Q: Is it normal to feel a certain way when first starting Li Shu?

The regulatory label documents several common adverse reactions that users may experience, including nervousness, dizziness, or sleeplessness. If these effects occur, or if any new symptoms appear, the official safety advice is to consult a healthcare professional and discontinue use as directed by the label.


Q: Is there a high chance of having a serious interaction with Li Shu?

The official label contains strict prohibitions against combining Li Shu with certain drug classes, such as Monoamine Oxidase Inhibitors ( MAOIs). Regulatory rules require the product to be completely avoided in these specific situations due to a defined risk of severe reactions like a hypertensive crisis.


Q: Does Li Shu interact with caffeine or alcohol?

Official labeling strictly warns against consuming three or more alcoholic drinks every day while using Li Shu. This constraint is due to the potential for severe, life-threatening liver damage associated with the Acetaminophen component. Official warnings do not explicitly address the potential for interaction with caffeine.


Q: Is Li Shu safe to take if I am already taking over-the-counter pain relievers?

The regulatory label strictly prohibits using Li Shu with any other medicine that contains Acetaminophen (prescription or nonprescription). This restriction is in place to prevent accidental overdose and the risk of severe liver injury. Users are advised to check the active ingredients of all other products being used to ensure safety.


Q: Are there different versions or strengths of Li Shu available?

The official product information confirms that Li Shu is manufactured in several forms, which typically include tablets, capsules, and liquid solutions. The regulatory label also specifies the precise strength of the active ingredients in each particular version of the product.


Q: Does the time of day I take Li Shu matter?

While the administration time can be with or without food, the label provides guidance on managing sleep disturbances. To help prevent a common side effect like trouble sleeping (insomnia), the official patient information suggests that the last dose of the day be taken several hours before bedtime.


Q: Does Li Shu cause 'brain fog' or difficulty concentrating?

The safety profile lists several central nervous system ( CNS) effects as possible adverse reactions, including dizziness, nervousness, confusion, and agitation. These documented effects may be related to what users commonly describe as 'brain fog' or difficulty concentrating.


Q: Can Li Shu affect my mood or behavior?

The regulatory safety profile includes documentation of adverse reactions categorized as Psychiatric Disorders. These effects involve changes such as nervousness, excitability, anxiety, and restlessness.


Q: What is the most common side effect reported for Li Shu?

Data gathered from adverse event reporting indicate that common side effects often include insomnia/sleeplessness, nervousness, headache, and dry mouth. Sleeplessness is frequently cited as one of the most common effects due to the decongestant component (Pseudoephedrine).


Q: Can Li Shu interact with herbal products or vitamins?

The official label advises that before starting use, users should ask a doctor or pharmacist about all other products being taken. This instruction applies broadly to all prescription drugs, nonprescription drugs, and herbal products to determine potential interaction risks.


Q: What are the signs of a rare but serious side effect from Li Shu?

Serious risks documented in regulatory warnings include signs of severe skin reactions (like blisters or rash) and signs of severe liver damage (such as yellowing of the skin/eyes, dark urine, or upper stomach pain). Official label information advises that if these signs occur, users should stop use immediately and seek medical help.


Q: How quickly is Li Shu expected to start having an effect?

Official data indicates that the decongestant component ( Pseudoephedrine) is typically expected to have an onset of action within about 30 minutes. The pain relief component ( Acetaminophen) often begins working in under an hour for pain relief.


Q: Does Li Shu have any risk of addiction or dependence?

The Pseudoephedrine component, while a controlled substance in some contexts, is classified by the Drug Enforcement Administration ( DEA) as a Non-Scheduled drug in this formulation. This classification indicates that the product does not carry the formal regulatory risk profile of a controlled substance associated with abuse or dependence.


Q: Can Li Shu be used by people who are sensitive to other medications?

The regulatory label directs users to avoid the product only if there is a known allergic reaction or hypersensitivity to the active ingredients ( Acetaminophen or Pseudoephedrine) or any of the inactive ingredients. The official documentation does not specifically address sensitivities to unrelated drugs.


Q: Are there any common foods that need to be avoided while taking Li Shu?

Official product information advises that the medication can be taken with or without food. There are no common foods that are strictly prohibited in the warning section. However, the use of alcohol is specifically highlighted and warned against due to the risk of liver damage.


Q: What should I do if a minor side effect of Li Shu doesn't go away?

The official Stop Use section advises that if side effects such as nervousness, dizziness, or sleeplessness occur or persist, the user should stop use and consult a doctor. This instruction is critical for any side effect that continues or worsens.


Q: Does Li Shu have any restrictions regarding driving or operating machinery?

Official label information indicates that caution is advised when driving a motor vehicle or operating machinery. This warning is due to the potential for the medicine to impair your thinking or reactions, or to cause side effects like dizziness or sleeplessness.


Q: Is Li Shu effective for all stages of the condition it treats?

The official indications state the medicine is for the temporary relief of specific common cold and flu symptoms (such as headache and congestion). Official indications state the medicine is not intended to treat the underlying cause or all stages of the condition.


Q: What is the half-life of Li Shu?

Pharmacokinetic data shows the two active components have different half-lives. The Acetaminophen component has a plasma half-life of approximately 2 to 3 hours. The Pseudoephedrine component has a highly variable half-life but often falls around 5 to 8 hours.


How should Li Shu be stored and disposed of?

Storage and Handling Requirements

Li Shu must be stored according to the conditions defined in the official regulatory labeling. The product requires storage at controlled room temperature, typically between 20 C and 25 C (68 F and 77 F), and must be protected from both moisture and excessive heat. The medicine should remain in its original container, which must be kept tightly closed to maintain its stability. Liquid forms of the medicine should not be frozen.

Child Safety and Disposal

It is an official requirement that Li Shu be stored out of the sight and reach of children and pets. Disposal of unused or expired product should utilize a drug take-back program. If one is unavailable, the medicine must be prepared for disposal in household trash, by mixing it with an unappealing substance and sealing it. The product must not be flushed down the toilet unless explicitly instructed by the label.

Attention! Always consult to a doctor or pharmacist before using pills or medicines.

Available in countries:

Equivalent of Li Shu found in:

A-Z Index: