Streptase

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Streptokinase

Method of action: Fibrinolytic

Treatment option: Angiography, Arterial thrombosis, Venography, Congestive Heart Failure, Pulmonary Embolism, Heart Failure, Heart Attack, Deep Vein Thrombosis, Thromboembolism

Medically reviewed

Rosario Oropesa

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 Streptase

Quick Facts

Property	Description
Active ingredient	Streptokinase
Form	Lyophilized powder for injection
Pharmacological class	Thrombolytic Agent, Fibrinolytic Drug
General purpose	Dissolution of blood clots in vessels
Origin	Biological (bacterial-derived polypeptide)

What Type of Medicine is Streptase?

Streptase is a medicinal preparation centered on the active component, Streptokinase, and is classified as a potent Thrombolytic Agent (or Fibrinolytic Drug). This classification establishes that the drug is designed to rapidly and directly initiate the breakdown of existing blockages, distinguishing it from anticoagulants that primarily work to prevent new clot formation. Streptokinase is clinically recognized for its therapeutic role. The clinical record confirms that this medicine is designed to quickly target and eliminate harmful obstructions within blood vessels.

Composition, Origin, and Preparation Form

The single active ingredient is Streptokinase, a polypeptide (protein) that is definitively biological in origin, derived from the culture of specific strains of beta-hemolytic streptococci bacteria. This characteristic means the molecule is a naturally occurring bacterial product, which is isolated and purified for therapeutic use. The medicine is supplied as a sterile, lyophilized powder (freeze-dried substance), which requires reconstitution into an intravenous solution immediately prior to administration. The route of administration is infusion directly into the bloodstream, a specialized delivery method essential for achieving quick clot dissolution in acute vascular events.

High-Level Action: The Principle of Fibrin Dissolution

Streptokinase works by acting as a powerful plasminogen activator within the circulatory system, forming a complex that converts the inactive enzyme plasminogen into its active form, plasmin. The resulting plasmin enzyme is highly specialized; its primary function is the molecular degradation of fibrin, the protein scaffolding that forms the structural foundation of a blood clot. Clinical observation indicates that the efficacy of Streptokinase in restoring blood flow is markedly higher when treatment is initiated sooner after the event onset, underscoring its role as a rapidly acting intervention. This confirms that the medication achieves its general benefit by breaking down the physical structure of the clot itself.

What side effects are possible with Streptase?

Possible Side Effects and Safety Information

The official regulatory safety profile for Streptase (Streptokinase) is dominated by the risk of hemorrhage (bleeding), which is inherent to its classification as a potent thrombolytic agent. Adverse reactions are classified by frequency and grouped into distinct System-Organ Classes (SOCs) in official government prescribing information.

Documented Adverse Reactions and Frequency

The most important safety concern is bleeding, which can range from common occurrences at injection sites to uncommon major gastrointestinal or urogenital hemorrhages. Rare but serious adverse reactions documented in the labeling include intracranial hemorrhage (bleeding in the brain) and anaphylactic shock.

Classification	Examples of Documented Effects (SOC)
Common	Fever, chills, headache, nausea, minor bleeding (Blood and Lymphatic Disorders)
Uncommon	Major hemorrhage, severe allergic reactions (Immune System Disorders)
Rare	Hemorrhagic stroke, serum sickness, non-cardiogenic pulmonary edema (Nervous/Immune/Respiratory Disorders)

Key Safety Constraints and Special Populations

Adverse effects are also categorized by the system affected, including Vascular Disorders such as hypotension (low blood pressure) and Cardiac Disorders related to reperfusion arrhythmias. Safety documentation notes that fever and chills are often observed as early reactions during or shortly after administration.

Due to the drug's bacterial origin, patients may develop anti-streptokinase antibodies. This is a major safety constraint, as it may reduce efficacy and increase the risk of allergic reactions upon re-administration within a typical 12-month period. For pregnant individuals, official safety notes indicate that the use of Streptokinase carries risks of bleeding complications that may lead to fetal death or abortion, particularly in the first 18 weeks of pregnancy.

Overdose and Emergency Response

Overdose and When to Seek Help

The official regulatory documentation describes an overdose of Streptase (Streptokinase) as an exaggeration of the drug's therapeutic effect, which is systemic fibrinolysis. This effect is principally manifested by haemorrhage, or uncontrolled bleeding, in various tissues and organs. Such manifestations can range from minor bleeding at injection sites to serious haemorrhagic complications, including intracranial haemorrhage or potentially fatal bleeding, which defines the urgency of the situation.

Official Emergency Response

In cases of suspected overdose, individuals must seek immediate medical attention or contact a Poison Control Center right away, as stated in the official prescribing information. Immediate actions required by regulators include the discontinuation of the Streptase infusion. Management of severe bleeding may involve administering a proteinase inhibitor or synthetic antifibrinolytics, such as Aminocaproic acid, and potentially replacing clotting factors to reverse the systemic fibrinolysis. Close monitoring for complications, including hypotension and arrhythmias, is required in the hospital setting.

Overdose Risk Classification
Primary Manifestation	Exaggerated fibrinolytic effect leading to haemorrhage.
Severity Classification	Capable of causing serious and fatal bleeding events.
Mandatory Action	Immediate medical attention is required.

Therapeutic Uses of Streptase

What Streptase Treats: Main Uses and Benefits

In clinical practice, Streptase is used in settings that involve acute or unstable symptom patterns caused by blood clots. The core therapeutic benefit supports the prompt management of these obstructions to address symptoms related to systemic imbalance and to support patient stability.

The medication is considered relevant therapeutic support primarily for conditions presenting with acute, distressing symptoms arising from major vessel blockages, such as Acute Myocardial Infarction (heart attack), massive Pulmonary Embolism, extensive Deep Vein Thrombosis (DVT), and Acute Arterial Occlusion causing limb-threatening lack of circulation. In these contexts, Streptase is commonly used to assist with maintaining functional stability during heightened symptoms.

“Applied across domains where additional symptomatic support is needed, this therapy assists with maintaining functional stability when symptoms are more noticeable.”

It is also relevant for specialized clot events, including Retinal Vessel Thrombosis, to provide supportive relief for sudden functional strain, and for clearing occluded vascular access catheters, supporting the continuity of essential treatment. The primary benefit supports the swift resolution of the circulatory challenge, which may assist with maintaining functional stability in the affected organ or limb.

Quick Fact: Relief for Acute Blockages
Symptom Category	Symptoms related to acute physiological strain
Typical Context	Used during phases when symptoms become temporarily overwhelming
Core Benefit	Provides support that helps ease the overall symptom burden caused by loss of circulation
Patient Focus	Assists with maintaining functional stability in acute vascular episodes

Regulatory References

Thrombolytic Therapy - StatPearls - NIH Bookshelf - NIH

Eligibility and Restrictions for Use

The eligibility for Streptase (Streptokinase) is strictly defined by regulatory agencies based on the risk of severe hemorrhage or potential lack of efficacy.

Populations for Whom Use is Contraindicated

Use is prohibited (contraindicated) for patients with a high risk of life-threatening bleeding, including those with:

Active internal bleeding or known clotting disorders.
Recent (e.g., within 2 months) cerebrovascular accident (stroke) or intracranial/intraspinal surgery.
Severe uncontrolled hypertension (e.g., systolic >200 mmHg or diastolic >100 mmHg).
Known intracranial neoplasm (brain disease or tumor).

Age and Condition-Specific Limitations

Population/Condition	Eligibility Status (Regulatory Basis)
Pediatric Population	Safety and efficacy have not been established; use is not recommended in children.
Prior Exposure	Not recommended if previously administered within the last 5 days to 12 months due to anti-streptokinase antibodies.
Pregnancy	Generally contraindicated; used only if potential benefit outweighs risk.
Recent Surgery/Trauma	Use is restricted following recent major surgery (within 10 days), delivery, or head trauma.
Severe Organ Disease	Use is restricted or conditional in patients with severe hepatic or renal disease.

What should I know about interactions with other medicines?

Streptase (Streptokinase) is a drug whose interaction profile is fundamentally defined by its effects on the body’s hemostatic (clotting) system. Interactions are considered clinically significant and revolve around an increased risk of bleeding.

Documented Interacting Categories

Category	Specific Examples Mentioned in Labeling
Anticoagulants	Heparin, Warfarin, and other fibrinolytic agents (e.g., Alteplase)
Antiplatelet Agents	Aspirin (Acetylsalicylic Acid / ASA), Clopidogrel

Practical Constraints and Requirements

Official regulatory documents state that the concomitant use of Streptase with anticoagulants or antiplatelet agents increases the potential for bleeding complications due to the agents’ combined effects on hemostasis. This includes drugs like Heparin, Warfarin, and Aspirin.

Another critical interaction constraint is related to repeated use: Because human exposure to streptococcal bacteria is common, antibodies to Streptokinase are often present. Therefore, Streptase may not be effective if administered more than five days after a prior administration, especially within a period of up to twelve months, as the existing antibodies can neutralize the drug.

A final constraint is procedural: Streptase should not have other medications added to its container or infusion solution.

Mechanism of Action

How Streptase Works: Mechanism of Action

The mechanism of action for Streptase (streptokinase) is strictly defined within the fibrinolytic system, where it functions as an enzyme activator operating within this system.

Plasminogen Activation and Complex Formation

Streptokinase initiates the thrombolytic cascade by binding tightly to plasminogen, a proenzyme naturally found in the bloodstream. This binding results in the formation of a Streptokinase-Plasminogen Complex. This initial interaction is the essential first step that leads to the final mechanistic consequence: fibrinolysis.

Conversion to Active Plasmin Enzyme

The newly formed complex acts as a catalyst, specifically as a serine protease, to convert other, unbound molecules of plasminogen into the active enzyme plasmin. This conversion and subsequent amplification of plasmin are mechanistic steps that increase fibrinolytic activity, leading to plasmin-mediated degradation.

Fibrin Breakdown (Thrombolysis)

The abundant plasmin enzyme then targets and hydrolyzes fibrin, the structural protein that forms the meshwork of a blood clot (thrombus). This direct enzymatic breakdown of fibrin into soluble fragments (Fibrin Degradation Products or FDPs) dismantles the clot structure. The final physiological consequence is the degradation of the fibrin matrix, resulting in the disintegration of the thrombus structure.

Dosage and Administration Information

Instruction Map: How to Use Streptase — Official Administration Guidelines

The usage of Streptase (Streptokinase) follows defined methods for its administration in acute care settings. The medication is supplied as a lyophilized powder that requires specific preparation before delivery.

Administration Scope

Category	Instruction and Method
Route of administration	Primarily Intravenous (IV) Infusion for systemic therapy; also Intracoronary Infusion for localized delivery, or Local Instillation for clearing occluded vascular access cannulae.
Dosing schedule	Acute Myocardial Infarction: A single dose of 1,500,000 IU. PE/DVT/Arterial Occlusion: A 250,000 IU loading dose followed by a 100,000 IU/hour maintenance infusion.
Timing in relation to meals	Not applicable; administration is for acute events.
Preparation requirements	The powder must be reconstituted using specific solutions, such as 0.9% Sodium Chloride Injection or 5% Dextrose Injection. Shaking the vial is strictly prohibited during reconstitution.
Age-group administration rules	Adult use is standardized, and guidelines generally do not specify explicit dose adjustments for older adults or pediatric patients.
Special procedural conditions	The infusion must be delivered via a controlled infusion pump to maintain precise hourly rates. The product must not be mixed with other medications in the same container.

Instruction Classifications (High-Level)

Classification	Principle
Administration method type	Intravenous
Frequency pattern	Single-course / Time-limited continuous infusion (not a recurring schedule)
Protocol basis	Governed by detailed clinical labeling and established medical protocols.
Use-context constraints	Administration is restricted to a controlled clinical setting with continuous patient monitoring.

Resulting Procedural Structure

Official step sequence:

Reconstitute the powder gently with the specified diluent to avoid foaming.
Administer the full single dose (for AMI) or the loading dose (for PE/DVT) over the specified short time limit (e.g., 30 to 60 minutes).
Initiate and maintain the continuous infusion at the fixed hourly rate (e.g., 100,000 IU/hour) immediately following the loading dose.
Continue the continuous infusion for the specified total duration, typically ranging from 24 to 72 hours depending on the specific use pattern.

Connection to the overall use protocol (2–4 sentences):

These instructions establish the use of Streptase as a standardized, acutely administered procedure where the dose, infusion rate, and total duration are precisely fixed. This protocol necessitates specialized clinical equipment and highly controlled administration to ensure adherence to the specific timeframes of the procedure.

Recent Clinical Evidence

Research Evidence / Overview of Studies for Streptase

Research Evidence for Acute Myocardial Infarction (Heart Attack)

The use of Streptase was evaluated in large-scale Randomized Controlled Trials (RCTs) and comprehensive Meta-Analyses involving adults who experienced an acute myocardial infarction (heart attack). These studies focused on measuring critical outcomes related to systemic or functional imbalance, specifically looking at changes in patient survival rates over short-term (e.g., 30 days) and intermediate intervals. Research also examined physical measures such as the degree of blood flow restoration in blocked coronary arteries and changes in heart pumping function (ventricular function).

Studies conducted during periods of increased symptom activity monitored outcomes based on the timing of administration; research highlights changes measured during the study period, showing patterns related to survival rates being observed following prompt intervention after symptom onset. While early research provides insight into short-term changes, comparative evidence is limited regarding its use alongside certain contemporary therapies or mechanical interventions.

Research Evidence for Major Clots (Pulmonary Embolism and Deep Vein Thrombosis)

Streptase was evaluated in trials exploring its use for two major conditions characterized by acute or disruptive episodes: massive Pulmonary Embolism (a sudden block in the lung arteries) and extensive Deep Vein Thrombosis (DVT) (major clots in the deep veins, often of the legs).

In these studies, researchers monitored outcomes related to the structural health of the vessels, such as the speed and extent of clot dissolution as assessed by specialized imaging. For DVT specifically, studies explored outcomes related to the long-term frequency of persistent vein damage, known as Post-Thrombotic Syndrome (PTS). Findings describe patterns observed in these studies, which often compared Streptase plus standard care to standard care alone. However, many of these research efforts are older, and the data for Streptase in this context are often analyzed together with evidence for other types of pharmacological agents.

Research Evidence for Acute Vascular Blockages (Arterial and Catheter Occlusions)

Research examined the potential use of Streptase in clearing blockages in other parts of the circulatory system, including acute peripheral arterial occlusions (sudden blocks in limb arteries) and occluded vascular access catheters (tubes used for essential medical treatments).

For these specific scenarios, the evidence base primarily consists of smaller clinical trials and case series. Studies focused on measuring immediate, short-term outcomes, such as the successful clearance of the catheter lumen or the objective measurement of blood flow return in the affected limb. Because the follow-up durations were limited, this evidence contributes to understanding immediate symptom patterns; however, the available data for long-term changes remain insufficient, and the certainty level remains low compared to the core indications.

Long-Term Studies and Follow-up Duration

Studies monitored patient responses over defined time intervals, with the most extensive data for heart attack being focused on the immediate and short-term period (up to about 30 days). For some indications, such as DVT, research explored outcomes up to several years to measure the frequency of complications like Post-Thrombotic Syndrome. However, long-term outcomes related to overall physical functioning, especially many years after the initial event, are not well characterized in the available research. Follow-up durations were limited in the acute settings, meaning research provides context but not individual predictions about durability of response beyond the immediate, acute phase.

Evidence in Specific Patient Groups

Research has explored the use of Streptase in certain defined populations. For instance, studies monitored outcomes in older adults with heart attack, reporting how symptoms evolved in this observed population. Studies were also designed to monitor patients based on the time delay between symptom onset and treatment. Conversely, studies exploring patient-reported outcomes describing perceived discomfort in certain groups, such as children or women who are pregnant or breastfeeding, are not documented.

Key Limitations and Areas of Uncertainty in the Research

A primary limitation of the research is that many of the large-scale pivotal studies for Streptase are historical and predate the routine use of certain modern interventions. This means that comparative evidence is limited against certain contemporary pharmacological agents or procedures. Additionally, evidence quality varies across studies, and some limitations include modest sample sizes in the DVT and peripheral occlusion trials. For many indications, the results apply only to the specific populations studied, and long-term effects beyond the initial observation period are not fully established. Research related to this topic is ongoing.

Key Studies & References

Thrombolytic Therapy - StatPearls - NIH Bookshelf (NBK557411)

Frequently Asked Questions (FAQ)

Common questions about Streptase (FAQ)

Q: How long after treatment does the increased risk of bleeding from Streptase last?

Regulatory documents describe that the drug's effect on blood clotting factors, such as reduced fibrinogen levels, has been observed to persist for periods of up to 12 to 24 hours after the infusion stops. This persistence contributes to the heightened risk of bleeding during this time.

Q: How long after the onset of symptoms is Streptase still considered effective?

Studies indicate that the greatest observed benefit for acute heart attack occurs when the drug is administered within 1 hour of symptom onset. Statistically significant benefits were observed up to six hours, and some benefit was seen up to 24 hours, confirming that prompt administration is essential for its noted effectiveness.

Q: Does having a recent streptococcal infection affect how well Streptase works?

Official documents note that a recent streptococcal infection, typically within the last six months, may lead to a reduced efficacy of Streptase. This is because the body may have already produced anti-streptokinase antibodies that can neutralize the drug.

Q: Are there any specific heart conditions that prevent the use of Streptase?

Regulatory sources list specific heart conditions as contraindications, which may prohibit treatment. These include active inflammation around the heart (pericarditis), certain structural issues like aortic dissection (a tear in the aorta wall), and uncontrolled severe high blood pressure.

Q: What kind of monitoring is typically done during and after Streptase infusion?

Continuous patient monitoring is required during and after administration. This typically involves frequent checks of blood pressure, heart rhythm (ECG), and vital signs. The medical team also monitors specific laboratory tests, such as aPTT and fibrinogen levels, which are measures used to assess the blood's clotting factors.

Q: How is the patient screened for eligibility before a doctor decides to use Streptase?

A thorough screening process is conducted by the medical team before administration, according to official guidelines. This check looks for known contraindications—conditions that prohibit use—such as active bleeding, recent trauma/surgery, a history of stroke, and severe uncontrolled high blood pressure.

Q: What types of abdominal or gastrointestinal issues are considered contraindications for Streptase?

Official prescribing information states that contraindications include a history of recent (within 10 days) serious bleeding in the stomach or intestines, as well as an active or recent (within two months) peptic ulcer. These conditions increase the risk of severe hemorrhage.

Q: Are there any foods or supplements that interact with Streptase?

Official product information typically focuses on interactions with other medications. Specific details regarding interactions with common foods or nutritional supplements are generally not addressed in the primary labeling. However, official information does mention that alcohol or tobacco use with certain medicines may cause interactions.

Q: Why is rapid administration important for the effectiveness of Streptase?

The effectiveness of Streptase is time-dependent. Research indicates that the survival rates observed in studies were higher when treatment was initiated sooner after the onset of symptoms. This urgency relates to the rapid progression of tissue damage that occurs when blood flow is blocked.

Q: Does the effectiveness of Streptase vary by the size or location of the blood clot?

Regulatory-cited clinical trials focus on location, with different efficacy measurements for clots in the heart versus those in the lungs. While the location clearly matters for outcomes, clot size is an area of ongoing research, as fibrin-specificity varies.

Q: Is there a maximum number of times a person can receive Streptase treatment?

Regulatory guidelines indicate that re-administering Streptase is not recommended within the first five days to twelve months after prior exposure. It is considered an absolute contraindication to re-administer it within six months due to the high risk of severe allergic reaction and neutralizing antibodies.

Q: Since Streptase comes from bacteria, can receiving it cause a new infection?

Official safety documents do not list the drug as a cause of new bacterial infection. However, because the drug is derived from bacteria, it may cause two non-infectious reactions: a fever (a common side effect) or the formation of antibodies which may cause allergic reactions.

Q: Is it normal to feel dizzy or lightheaded after receiving Streptase?

Official safety documents list dizziness and lightheadedness as documented side effects that may occur. These symptoms are often associated with a drop in blood pressure (hypotension), which is a common safety risk noted in the drug's prescribing information.

Q: What are the signs of a severe allergic reaction to Streptase that patients should be aware of?

The official safety profile notes the potential for severe allergic reactions, including anaphylactic shock. Signs that have been documented may include the appearance of hives, swelling of the face, lips, or throat, difficulty breathing, feeling lightheaded, and an abnormally fast heartbeat.

Q: Are there any common over-the-counter pain relievers that interact with Streptase?

Official information indicates that taking Aspirin (Acetylsalicylic Acid / ASA), which is present in some common pain relievers, is noted to potentially increase the risk of bleeding when used with Streptase. Both agents affect the blood's ability to clot, and their combined effect may require caution.

Q: Is Streptase generally recommended for pregnant or breastfeeding patients?

Official documentation states that Streptase is generally not recommended during pregnancy and is only administered when the potential benefit is judged to outweigh the known risks. Furthermore, regulatory sources indicate there are no data available on whether the drug is excreted into human milk during breastfeeding.

Q: Can a fever after Streptase treatment be a sign of a serious complication?

Official safety information notes that fever and chills are documented as common side effects that often occur as early reactions during or shortly after treatment. However, an elevated temperature may also be a symptom of a severe allergic reaction, which is classified as an uncommon but serious complication.

Q: What research is available about the long-term outcomes after being treated with Streptase?

Research has primarily focused on immediate and short-term outcomes, such as the reduction of mortality at 30 days and the impact on heart function. Long-term outcomes related to overall physical functioning after treatment are generally not well characterized in the available research.

Q: What is the difference between Streptase and alteplase (tPA) at a high level?

Official information indicates that Streptase is bacterial-derived, a characteristic that is associated with a risk of allergic reactions. Alteplase is made using recombinant DNA technology and is generally considered more fibrin-specific (more targeted to the clot).

Q: Are there specific safety concerns regarding the use of Streptase in patients with severe kidney problems?

Official prescribing information lists severe renal (kidney) disease as a condition that restricts or makes the use of Streptase conditional. This restriction necessitates careful consideration during the screening process.

Q: Is it possible for Streptase to cause internal bleeding that is not visible externally?

Regulatory documents indicate that Streptase can cause internal bleeding that may not be visible externally. The official safety profile specifically documents risks of hemorrhage in internal areas, including intracranial hemorrhage (bleeding in the brain) and major bleeding in the gastrointestinal and urogenital tracts.

How should Streptase be stored and disposed of?

Official Storage and Disposal Requirements for Streptase

The storage and disposal guidelines for Streptase (Streptokinase) are strictly defined by regulatory labeling to maintain product stability and safety.

Storage Conditions

Unopened Vials: The lyophilized powder must be stored at Controlled Room Temperature, specifically between 15 C and 30 C (59 F and 86 F).
Reconstituted Solution: If the solution is not used immediately, it must be stored under refrigeration at 2 C to 8 C (36 F to 46 F). The solution must be used within eight hours of reconstitution.

Handling and Safety Rules

Container Constraint: Regulatory documents explicitly prohibit adding any other medication to the Streptase container.
Child Safety: Like all medicines, Streptase must be kept out of the sight and reach of children.

Disposal Instructions

Any unused product or waste material must be disposed of in accordance with local requirements and professional procedures for pharmaceutical waste. It must not be discarded into regular household waste or drains.

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