Acetaminophen for Postoperative Pain

Age: 18+

Sex: Any

Trial Phase: Phase 4

Sponsor: Stanford University

Disqualifiers: Chronic pain, Pregnancy, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Prior Safety Data This treatment has passed at least one previous human trial

Compensation: Varies

Number of Visits: Unknown

Duration: 48 hours

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial examines the effectiveness of acetaminophen for pain relief after lumbar spine fusion surgery. Researchers aim to determine whether oral acetaminophen is more effective than IV administration. Participants will receive either oral acetaminophen or an IV infusion for two days post-surgery. The study seeks individuals scheduled for lumbar spine fusion surgery who can swallow pills and have no medical contraindications to acetaminophen. As a Phase 4 trial, this research explores how this FDA-approved and effective treatment can benefit more patients.

Do I need to stop my current medications for the trial?

The trial information does not specify whether you need to stop taking your current medications. It's best to discuss this with the trial coordinators or your doctor.

What is the safety track record for acetaminophen?

A previous study found that taking acetaminophen orally reduced the need for opioids after surgery, suggesting it is well-tolerated, as fewer opioids lead to fewer side effects. Another study demonstrated that a single dose of oral acetaminophen provided effective pain relief for many patients for about four hours post-surgery.

Research has also shown that acetaminophen administered through an IV is safe and effective. One study found that patients receiving IV acetaminophen experienced less post-surgical pain and required fewer additional pain medications. Another study indicated that using IV acetaminophen helped shorten hospital stays by reducing opioid use.

Both oral and IV acetaminophen have been shown to control pain after surgery without major safety concerns, supported by their common use and approval for pain management. ^{1 2 3 4 5}

Why are researchers enthusiastic about this study treatment?

Researchers are excited about acetaminophen for postoperative pain because it offers versatile administration options that can be tailored to patient needs. Unlike typical pain medications that might rely heavily on opioids, acetaminophen provides an alternative with fewer side effects and lower dependency risks. This trial compares oral and intravenous delivery methods, offering flexibility and potentially faster pain relief through intravenous administration. This variety in administration could enhance patient comfort and pain management following spine surgery, setting acetaminophen apart from the standard opioid-based care.

What is the effectiveness track record for acetaminophen in treating postoperative pain?

This trial will compare the effectiveness of oral and intravenous acetaminophen in managing postoperative pain. Studies have shown that both forms effectively manage pain after surgery. A single dose of oral acetaminophen relieves pain for about half of the patients for around four hours and reduces the need for stronger painkillers, like opioids, while lessening postoperative nausea. Research indicates that intravenous acetaminophen improves pain relief and further reduces opioid use, enhancing patient comfort after surgery. Comparisons between oral and intravenous forms suggest they offer similar pain relief. Overall, acetaminophen is a reliable option for controlling postoperative pain. ^{1 4 6 7 8}

Who Is on the Research Team?

Atman Desai, MD

Principal Investigator

Stanford University

Are You a Good Fit for This Trial?

This trial is for patients undergoing lumbar spine fusion surgery who need pain control. Specific eligibility criteria are not provided, but typically participants must meet certain health standards and not have conditions that would interfere with the study or pose a risk.

Inclusion Criteria

I am scheduled for a specific back surgery involving 1-3 spinal levels.

Able to provide written informed consent

Must be able to swallow pills

Exclusion Criteria

Pregnancy

I have chronic pain not caused by surgery.

I have had emergency surgery.

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

1-2 weeks

Treatment

Participants receive either oral or intravenous acetaminophen for 48 hours post-surgery

48 hours

In-hospital stay

Postoperative Monitoring

Participants are monitored for pain intensity and opioid consumption until discharge

Up to 10 days

Follow-up

Participants' quality of life and any treatment-related adverse effects are assessed

1 month

What Are the Treatments Tested in This Trial?

Interventions

• Acetaminophen

Trial Overview The study is testing the effectiveness of oral versus intravenous acetaminophen in managing postoperative pain after lumbar spine surgery. It includes a placebo group for each administration method to compare results.

How Is the Trial Designed?

Group I: Intravenous Acetaminophen 1000mg Experimental Treatment 2 Interventions

Participants take acetaminophen infusion and oral placebo for 48 hours within 2 hours after their spine surgery

Group II: Oral Acetaminophen 1000mg Active Control 2 Interventions

Participants take oral acetaminophen and placebo infusion for 48 hours within 2 hours after their spine surgery

Who Is Running the Clinical Trial?

Stanford University

Lead Sponsor

Trials

2,527

Recruited

17,430,000+

Citations

1. pubmed.ncbi.nlm.nih.gov pubmed.ncbi.nlm.nih.gov/21114616/

A literature review of randomized clinical trials ... Twelve of the 14 placebo studies found that IV acetaminophen patients had improved analgesia. Ten of those 14 studies reported less opioid consumption, a lower ...

2. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC4149981/

The Effect of Intravenous Paracetamol on Postoperative Pain ... In fact, their study also showed that intravenous paracetamol not only effectively reduced postoperative pain severity but also increased patients' ...

3. sciencedirect.com sciencedirect.com/science/article/abs/pii/S1878875019329043

Systematic Review and Meta-Analysis of Randomized ... Several lines of evidence have demonstrated that intravenous acetaminophen reduces the opioid requirement and increases the postoperative comfort level.12,13 ...

4. cochrane.org cochrane.org/evidence/CD007126_intravenous-paracetamol-acetaminophen-pain-after-surgery-adults-and-children

Intravenous paracetamol (acetaminophen) for pain after ... We found high quality evidence that IV paracetamol or IV propacetamol provided pain relief for four hours for about 36% of people versus 16% of ...

5. wjgnet.com wjgnet.com/2218-5836/full/v16/i4/104452.htm

Effectiveness of oral vs intravenous acetaminophen on ... The results demonstrated that oral acetaminophen was comparable to intravenous acetaminophen with regard to VAS scores at 24 h and 48 h (P = ...

6. nature.com nature.com/articles/s41598-025-20499-4

Effect of the intravenous acetaminophen clinical pathway ... Effect of the intravenous acetaminophen clinical pathway on postoperative analgesia in spinal fusion surgery.

7. frontiersin.org frontiersin.org/journals/pharmacology/articles/10.3389/fphar.2022.909572/full

Efficacy and safety of intravenous acetaminophen (2 g/day) ... We have demonstrated that intravenous administration of 500 mg acetaminophen every 6 h in 24 h postoperatively reduced the supplemental intravenous morphine ...

8. link.springer.com link.springer.com/article/10.1007/s12325-016-0438-y

Estimating the Effect of Intravenous Acetaminophen for ... This investigation indicates that reducing opioid use and including IV APAP for postoperative pain management has the potential to decrease LOS, ...