What is the recommended intravenous bolus administration rate and timing for Tenecteplase (TNK) in acute ST‑segment‑elevation myocardial infarction and acute ischemic stroke?

Tenecteplase (TNK) Administration Rate and Timing

Tenecteplase is administered as a single intravenous bolus over 5-10 seconds, with weight-based dosing that differs between STEMI (0.5 mg/kg, maximum 50 mg) and acute ischemic stroke (0.25 mg/kg, maximum 25 mg), and should be given as rapidly as possible after diagnosis is confirmed. 1, 2, 3

Administration Rate

STEMI (ST-Elevation Myocardial Infarction)

• Administer as a single IV bolus over 5-10 seconds using the following weight-based dosing: 1, 3

  • 30 mg for weight <60 kg
  • 35 mg for 60-69 kg
  • 40 mg for 70-79 kg
  • 45 mg for 80-89 kg
  • 50 mg for ≥90 kg

• This single-bolus administration contrasts sharply with alteplase, which requires a 90-minute infusion regimen. 1

• The pharmacokinetic rationale: tenecteplase has a 22-minute initial half-life and 65-132 minute terminal half-life—approximately 4-fold slower clearance than alteplase—allowing the entire dose to be given as a rapid bolus. 3, 4

Acute Ischemic Stroke

• Administer as a single IV bolus with a dose of 0.25 mg/kg (maximum 25 mg) over 5-10 seconds. 2, 5

• The American Heart Association/American Stroke Association suggests tenecteplase might be considered as an alternative to alteplase in patients with minor neurological impairment and no major intracranial occlusion (Class IIb, Level of Evidence B-R). 1, 2

• Critical distinction: The stroke dose (0.25 mg/kg) is half the STEMI dose (0.5 mg/kg), based on trials demonstrating superior recanalization and improved 3-month outcomes at this lower dose for large vessel occlusions. 2, 5

Timing of Administration

STEMI Context

• Initiate tenecteplase immediately upon STEMI diagnosis when primary PCI cannot be achieved within 2 hours from first medical contact. 1

• If at a non-PCI-capable hospital and symptoms have been present <12 hours, fibrinolytic therapy with tenecteplase is recommended to reduce death and reinfarction when device activation cannot occur within 2 hours. 1

• The weight-adjusted bolus should be given as soon as the diagnosis is confirmed and contraindications are excluded. 1

Acute Ischemic Stroke Context

• Treatment should be initiated as soon as possible after patient arrival and CT scan, with every effort made to minimize door-to-needle times. 2

• Tenecteplase has been studied up to 4.5 hours after stroke onset, though the 0.25 mg/kg dose is specifically recommended for use within this window. 1, 2, 6

• The single-bolus administration offers significant workflow advantages, particularly in centers considering endovascular therapy or patient transfer. 2

Key Practical Advantages

• No infusion pump required: Unlike alteplase's 90-minute infusion, tenecteplase is pushed as a bolus over seconds, eliminating infusion-related delays and errors. 1, 2

• Simplified dosing: Weight-based tiered dosing (rather than continuous calculation) reduces medication errors. 1

• Faster administration: The entire dose is delivered in <10 seconds versus 90 minutes for alteplase. 3, 4

Critical Pitfalls to Avoid

• Do not use STEMI dosing for stroke: The 0.5 mg/kg STEMI dose has not been proven safe or effective for stroke; use only 0.25 mg/kg (maximum 25 mg) for acute ischemic stroke. 2, 5

• Do not delay for precise weight: Use estimated weight if necessary to avoid treatment delays; the tiered dosing system accommodates reasonable weight estimation. 1

• Do not administer as an infusion: Tenecteplase must be given as a rapid bolus, not diluted or infused over time. 1, 3

• Verify indication-specific contraindications: Both STEMI and stroke share similar absolute contraindications (intracranial hemorrhage, recent significant trauma, uncontrolled hypertension >180/110 mmHg), but these may be superseded in life-threatening situations like PE-related cardiac arrest. 1, 7

Ancillary Anticoagulation Timing

• For STEMI patients <75 years with normal renal function: Administer enoxaparin 30 mg IV bolus immediately with or after tenecteplase, followed by 1.0 mg/kg subcutaneously every 12 hours. 8

• For STEMI patients ≥75 years or with renal dysfunction: Use unfractionated heparin instead—60 U/kg IV bolus (maximum 4,000 U) followed by 12 U/kg/hour infusion (maximum 1,000 U/hour), targeting aPTT 1.5-2.0 times control. 1, 8

• For stroke patients: Anticoagulation protocols follow standard stroke guidelines and are not routinely initiated immediately with tenecteplase. 1