Painrel

Uses

Painrel injections and tablets are used for the short-term management of moderate to severe acute post-operative pain.

Painrel is also used to associated treatment for these conditions: Acute Migraine, Cystoid Macular Edema, Eye Pain, Inflammation, Ocular Itching, Pseudophakic Cystoid Macular Edema, Acute Pericarditis, Acute, moderate Pain, Acute, severe Pain, Chronic aphakic cystoid macular edema, Intraoperative miosis, Postoperative ocular pain

How Painrel works

Painrel inhibits key pathways in prostaglandin synthesis which is crucial to it's mechanism of action. Although ketorolac is non-selective and inhibits both COX-1 and COX-2 enzymes, it's clinical efficacy is derived from it's COX-2 inhibition. The COX-2 enzyme is inducible and is responsible for converting arachidonic acid to prostaglandins that mediate inflammation and pain. By blocking this pathway, ketorolac achieves analgesia and reduces inflammation. Painrel is administered as a racemic mixture; however, the "S" enantiomer is largely responsible for it's pharmacological activity.

Dosage

Painrel dosage

Painrel Tablet-

Painrel Tablet isrecommended for short-term use only (up to 7 days) and are not recommended for chronic use. 10 mg every 4 to 6 hours as required. Doses exceeding 40 mg/day are not recommended. For patients receiving parenteral Painrel tromethamine, and who are converted to Painrel tromethamine oral tablets, the total combined daily dose should not exceed 90 mg (60 mg for the elderly, renally impaired patients and patients less than 50 kg) and the oral component should not exceed 40 mg on the day the change of formulation is made. Patients should be converted to oral treatment as soon as possible.

Painrel injection-

Painrel injection may be used as a single or multiple doses, on a regular or when necessary schedule for the management of moderately severe, acute pain that requires analgesia at the opioid level, usually in a postoperative setting. When administering Painrel injection, the IV bolus must be given over no less than 15 seconds. The IM administration should be given slowly and deeply into the muscle. The analgesic effect begins within 30 minutes with maximum effect in 1 to 2 hours after dosing IV or IM. Duration of analgesic effect is usually 4 to 6 hours. Single-Dose Treatment: The following regimen should be limited to single administration use only.

IM Dosing (Adult):

• Patients <65 years of age: One dose of 60 mg.
• Patients >65 years of age, renally impaired and/or less than 50 kg of body weight: One dose of 30 mg.

IV Dosing (Adult):

• Patients <65 years of age: One dose of 30 mg.
• Patients >65 years of age, renally impaired and/or less than 50 kg of body weight: One dose of 15 mg.

IV or IM Dosing (2 to 16 years of age):

• IM Dosing: One dose of 1 mg/kg up to a maximum of 30 mg.
• IV Dosing: One dose of 0.5 mg/kg up to a maximum of 15 mg.

Multiple-Dose Treatment (IV or IM):

• Patients <65 years of age: The recommended dose is 30 mg Painrel injection every 6 hours. The maximum daily dose should not exceed 120 mg. Patients >65 years of age, renally impaired patients and patients less than 50 kg: The recommended dose is 15 mg Painrel injection every 6 hours. The maximum daily dose for these populations should not exceed 60 mg. For breakthrough pain, do not increase the dose or the frequency of Painrel Tromethamine.
• Conversion from Parenteral to Oral Therapy: Painrel tablets may be used either as monotherapy or as follow-on therapy to parenteral Painrel. When Painrel tablets are used as a follow-on therapy to parenteral Painrel, the total combined daily dose of ketorolac (oral + parenteral) should not exceed 120 mg in younger adult patients or 60 mg in elderly patients on the day the change of formulation is made. On subsequent days, oral dosing should not exceed the recommended daily maximum of 40 mg. Painrel IM should be replaced by Painrel tablet as soon as feasible. The total duration of combined parenteral andoral treatment should not exceed 5 days.

Painrel Nasal spray-

• Adults weighing 50 kg or more: 31.5 mg or 2 spray in each nostril every 6 to 8 hours. Your doctor may adjust your dose if needed. However, the dose is not more than 126 mg (a total of 8 sprays) per day.
• Older adults and adults weighing less than 50 kg:15.75 mg or 1 spray in only one nostril every 6 to 8 hours. However, the dose is usually not more than 63 mg (a total of 4 sprays) per day.
• Children: Use and dose must be determined by your doctor.

Side Effects

Commonly occurring side-effects are nausea, vomiting, gastro intestinal bleeding,melaena, peptic ulcer, pancreatitis, anxiety, drowsiness, dizziness, headache, hallucinations,excessive thirst, inability to concentrate, insomnia, malaise, fatigue, pruritus, urticaria, skin photosensitivity, Lyell's syndrome, Stevens-Johnson syndrome, flushing, bradycardia, hypertension, palpitations, chest pain, infertility in female, dyspnoea, asthma, pulmonary oedema, fever, injection site pain.

Toxicity

The rate of adverse effects increases with higher doses of ketorolac. The most frequently observed adverse effects in patients occurring with an incidence of greater than 10% include: abdominal pain, dyspepsia, nausea, and headaches. Most adverse effects associated with short term use are mild in nature, related to the gastrointestinal tract and nervous system, and occur in roughly 39% of patients. Common symptoms of ketorolac overdose include nausea, vomiting, epigastric pain, gastrointestinal bleeding, lethargy and drowsiness. More rare symptoms of overdose include acute renal failure, hypertension, respiratory depression, and coma.

Painrel is classified as Pregnancy Category C since there is a lack of evidence demonstrating safety in pregnant women. NSAIDs including ketorolac increase the risk of premature closure of the fetal ductus arteriosus in the 3rd trimester; therefore, beginning at 30 weeks gestation, pregnant women should avoid ketorolac.

Painrel has been shown to be excreted in breast milk, and although available data has not demonstrated any adverse effects in nursing infants, practitioners should proceed with caution when suggesting ketorolac for nursing mothers. The benefits should outweigh the risks and the mother should be counselled to monitor the infant closely and to contact the infant's healthcare provider should any adverse effects arise.

Women who are trying to conceive are not advised to take ketorolac since it's effect on prostaglandin synthesis may impair fertility.

Precaution

Patients over the age of 65 years may be at a greater risk of experiencing adverse events than younger patients. Painrel tromethamine can cause gastro-intestinal irritation, ulcers or bleeding in patients with or without a history of previous symptoms. Bronchospasm may be precipitated in patients with a history of asthma. Since ketorolac tromethamine and its metabolites are excreted primarily by the kidney, patients with moderate to severe impairment of renal function (serum creatinine greater than 160 micromol/l) should not receive. Fluid retention and oedema have been reported with the use of Painrel tromethamine.

Interaction

Painrel tromethamine should not be used with other NSAIDs or in patients receiving aspirin because of the potential for additive side effects. Care should be taken when administering Painrel tromethamine with anti-coag ulants since co-administration may cause an enhanced anti-coagulant effect. Painrel tromethamine and other non-steroidal anti-inflammatory drugs can reduce the anti hypertensive effect of beta-blockers and may increase the risk of renal impairment when administered concurrently with ACE inhibitors, particularly in volume depleted patients. Caution is advised when methotrexate is administered concurrently, since some prostaglandin synthesis inhibiting drugs have been reported to reduce the clearance of methotrexate, and thus possibly enhance its toxicity. Probenecid should not be administered concurrently with ketorolac tromethamine because of increases in ketorolac plasma level and half-life.

Food Interaction

• Take with food. Food reduces GI irritation.

Painrel Alcohol interaction

[Moderate] GENERALLY AVOID:

The concurrent use of aspirin or nonsteroidal anti-inflammatory drugs (NSAIDs) and ethanol may lead to gastrointestinal (GI) blood loss.

The mechanism may be due to a combined local effect as well as inhibition of prostaglandins leading to decreased integrity of the GI lining.

Patients should be counseled on this potential interaction and advised to refrain from alcohol consumption while taking aspirin or NSAIDs.

Painrel Hypertension interaction

[Major] Fluid retention and edema have been reported in association with the use of nonsteroidal anti-inflammatory drugs (NSAIDs).

Therapy with NSAIDs should be administered cautiously in patients with preexisting fluid retention, hypertension, or a history of heart failure.

Blood pressure and cardiovascular status should be monitored closely during the initiation of NSAID treatment and throughout the course of therapy.

[Moderate] Nonsteroidal anti-inflammatory drugs (NSAIDs), including topicals, can lead to new onset of hypertension or worsening of preexisting hypertension, either of which can contribute to the increased incidence of cardiovascular events.

NSAIDs should be used with caution in patients with hypertension.

Blood pressure should be monitored closely during the initiation of NSAID therapy and throughout the course of therapy.

Painrel Drug Interaction

Moderate: duloxetine, duloxetineUnknown: diphenhydramine, diphenhydramine, albuterol / ipratropium, albuterol / ipratropium, lvp solution, lvp solution, cyclobenzaprine, cyclobenzaprine, pregabalin, pregabalin, acetaminophen / hydrocodone, acetaminophen / hydrocodone, acetaminophen, acetaminophen, cyanocobalamin, cyanocobalamin, cholecalciferol, cholecalciferol

Painrel Disease Interaction

Major: GI toxicity, platelet aggregation inhibition, renal dysfunction, asthma, fluid retention, rash, thrombosisModerate: anemia, heart failure, hepatotoxicity, hyperkalemia, hypertension

Volume of Distribution

The apparent volume of distribution of ketorolac in healthy human subjects is 0.25 L/kg or less.

Elimination Route

Painrel is rapidly, and completely absorbed after oral administration with a bioavailability of 80% after oral administration. Cmax is attained 20-60 minutes after administration, and after intramuscular administration, the area under the plasma concentration-time curve (AUC) is proportional to the dose administered.

After intramuscular administration, ketorolac demonstrates a time to maximal plasma concentration (tmax) of approximately 45-50 minutes, and a tmax of 30-40 minutes after oral administration. The rate of absorption may be reduced by food; however, the extent of absorption remains unaffected.

Half Life

Painrel tromethamine is administered as a racemic mixture, therefore the half-life of each enantiomer must be considered. The half life of the S-enantiomer is ~2.5 hours, while the half life of the R-enantiomer is ~5 hours. Based on this data, the S enantiomer is cleared about twice as fast as the R enantiomer.

Clearance

The plasma clearance of ketorolac is 0.021 to 0.037 L/h/kg. Further, studies have illustrated that clearance of oral, IM and IV doses of ketorolac are comparable which suggests linear kinetics. It should also be noted that clearance in children is about double the clearance found in adults.

Elimination Route

Painrel is primarily renally eliminated and approximately 92% of the dose can be recovered in the urine with 60% of this proportion recovered unchanged, and 40% recovered as metabolites. In addition 6% of a single dose is eliminated in the feces.

Pregnancy & Breastfeeding use

Safety in human pregnancy has not been established. Painrel has been detected in human milk at low levels. Painrel is therefore contraindicated during pregnancy, labour or delivery, or in mothers who are breast feeding.

Contraindication

Painrel Tromethamine is contraindicated in patients with known hypersensitivity to NSAIDs and any of the components of Painrel Tromethamine. Moreover, the patient with the history of asthma, nasal polyp, angioedema, peptic ulcer and bleeding, bleeding disorders are contraindicated for this drug.

Acute Overdose

Symptoms: Abdominal pain, nausea, vomiting, hyperventilation, peptic ulceration, erosive gastritis and renal dysfunction.

Management: Symptomatic and supportive treatment. Consider gastric lavage or admin of activated charcoal within 1 hr of ingestion.

Storage Condition

Tablet & injection should be store in a cool & dry place, protect from light & moisture.

Innovators Monograph

You find simplified version here Painrel