What is the recommended intravenous ketorolac dose for adults, including adjustments for patients aged 65 years or older or weighing less than 50 kg, and what are its contraindications?

Intravenous Ketorolac Dosing for Adults

For adults under 65 years, the standard IV dose is 30 mg as a single dose or 30 mg every 6 hours for multiple dosing (maximum 120 mg/day), while patients ≥65 years, weighing <50 kg, or with renal impairment require dose reduction to 15 mg every 6 hours (maximum 60 mg/day), with treatment never exceeding 5 consecutive days regardless of route. 1

Standard Adult Dosing (Age <65 years, Weight ≥50 kg)

Single-Dose Regimen

• 30 mg IV administered as a single bolus over at least 15 seconds 1
• Analgesic effect begins in approximately 30 minutes with maximum effect at 1-2 hours 1
• Duration of analgesia typically 4-6 hours 1

Multiple-Dose Regimen

• 30 mg IV every 6 hours 1
• Maximum daily dose: 120 mg 1
• Treatment duration must not exceed 5 days total (combined IV and oral routes) 1

Dose Adjustments for High-Risk Populations

Three specific patient groups require mandatory 50% dose reduction: patients ≥65 years old, patients weighing <50 kg (110 lbs), and patients with moderately elevated serum creatinine 1, 2

Elderly (≥65 years), Low Body Weight (<50 kg), or Renal Impairment

Single-Dose Regimen

• 15 mg IV as a single dose 1

Multiple-Dose Regimen

• 15 mg IV every 6 hours 1
• Maximum daily dose: 40-60 mg 2, 1
• The National Comprehensive Cancer Network specifically recommends a 40 mg/day maximum for elderly patients 2

Rationale for Dose Reduction

• Elderly patients (≥60 years) face significantly elevated risk for NSAID-related renal toxicity, gastrointestinal bleeding/perforation, and cardiovascular events 2, 1
• Pharmacokinetic studies demonstrate reduced clearance in elderly patients, leading to drug accumulation 3
• Renal insufficiency causes plasma accumulation of ketorolac even at standard doses 3

Critical Duration Limitation

The 5-day maximum is absolute and applies to total cumulative therapy, not per-month allowances. 1, 4

• Combined IV and oral ketorolac must not exceed 5 consecutive days 1
• Repeated 5-day courses within the same month are not evidence-based and should be avoided 4
• "Cycling" on and off ketorolac lacks clinical support and is not recommended 4
• Increasing dose or frequency beyond label recommendations increases serious adverse event risk without improving efficacy 1

Administration Technique

• IV bolus must be given over at least 15 seconds 1
• Do not mix ketorolac in small volumes (e.g., syringes) with morphine, meperidine, promethazine, or hydroxyzine due to precipitation 1
• Correct hypovolemia before administering ketorolac 1

Absolute Contraindications

Ketorolac is contraindicated in the following situations 1, 4:

• Active peptic ulcer disease or recent gastrointestinal bleeding/perforation 1, 4
• History of peptic ulcer disease or GI bleeding 1
• Advanced renal impairment or patients at risk for renal failure due to volume depletion 1
• Suspected or confirmed cerebrovascular bleeding 1
• Hemorrhagic diathesis, incomplete hemostasis, or high bleeding risk 1
• Thrombocytopenia or concurrent anticoagulant/antiplatelet therapy 4, 1
• Aspirin/NSAID-induced asthma or prior hypersensitivity reactions to NSAIDs 1, 4
• Coronary artery bypass graft (CABG) surgery setting 1
• Labor and delivery (may adversely affect fetal circulation and inhibit uterine contractions) 1
• Concurrent use with aspirin or other NSAIDs 1
• Intrathecal or epidural administration 1

Monitoring Requirements

Baseline assessment before initiating ketorolac should include: 2, 4

• Renal function tests (BUN, creatinine) 2, 4
• Blood pressure measurement 2, 4
• Complete blood count 2, 4
• Liver function studies 4
• Fecal occult blood testing 4

Ongoing monitoring during therapy: 4

• Repeat monitoring every 3 months if extended use is considered (though duration should not exceed 5 days) 2
• Discontinue if liver function studies increase, BUN/creatinine doubles, or hypertension develops or worsens 4

High-Risk Drug Interactions

Avoid concurrent use with: 2, 4

• Other NSAIDs (cumulative toxicity risk) 2, 1
• SSRIs and SNRIs (significantly elevated bleeding risk) 2, 4
• Anticoagulants and antiplatelets (major bleeding risk) 4, 1
• Nephrotoxic drugs (increased renal toxicity) 4

Relative Contraindications Requiring Caution

• Heart failure and hypertension 4
• Age >60 years with history of significant alcohol use 4
• Hepatic dysfunction 4
• Concurrent ACE inhibitors or diuretics in elderly patients 4
• History of cardiovascular disease or high cardiovascular risk 4

Rescue Analgesia and Alternatives

• For breakthrough pain, do not increase ketorolac dose or frequency 1
• Consider supplementing with low-dose opioids as needed unless contraindicated 1
• Recent evidence demonstrates that 10 mg IV ketorolac provides equivalent analgesia to 30 mg with similar adverse effect profiles, suggesting lower doses may be preferable 5

When ketorolac is contraindicated or unsuitable, safer alternatives include: 4

• Acetaminophen up to 4 g daily (monitor blood pressure effects) 4
• Low-dose oral opioids 4
• Opioids without active metabolites (methadone, buprenorphine, fentanyl) for patients with renal concerns 4
• COX-2 selective inhibitors for patients with high GI risk but without cardiovascular risk 4

Common Pitfalls to Avoid

• Never exceed 5 days total duration regardless of clinical response 1
• Do not use higher doses in elderly/low-weight patients thinking it will improve analgesia—it only increases toxicity 1
• Avoid in patients on anticoagulation even with "therapeutic" INR levels 1
• Do not administer as prophylactic analgesia before major surgery 1
• Recognize that ketorolac carries one of the highest GI toxicity risks among NSAIDs, especially with prolonged use 4, 6