Non-narcotic analgesics. Problems of overdosage

Sublingual ketorolac and sublingual piroxicam are equally effective for postoperative pain, trismus, and swelling management in lower third molar removal

OBJECTIVE

Lower third molar removal provides a clinical model for studying analgesic drugs. The present study's aim was to compare the clinical efficacy of sublingual ketorolac and sublingual piroxicam in managing pain, trismus and swelling after lower third molar extraction in adult volunteers.

STUDY DESIGN

In this double-blinded, randomized, crossover investigation, 47 volunteers received for 4 days ketorolac sublingually (10 mg 4 times daily) and piroxicam sublingually (20 mg once daily) during 2 separate appointments after lower third molar extraction of symmetrically positioned lower third molars. A surgeon evaluated objective parameters (surgery duration, mouth opening, rescue analgesic medication, and facial swelling) and volunteers documented subjective parameters (postoperative pain and global evaluation), comparing postoperative results for a total of 7 days after surgery. The means of the objective and subjective parameters were compared for statistical significance (P < .05).

RESULTS

Volunteers reported low pain scores during the postoperative period when treated with either sublingual ketorolac or piroxicam. Also, volunteers ingested similar amounts of analgesic rescue medication (paracetamol) when they received either drug sublingually (P > .05). Additionally, values for mouth openings measured just before surgery and immediately after suture removal 7 days later were similar among volunteers (P > .05), and the type of nonsteroidal antiinflammatory drug (NSAID) used in this study showed no significant differences between swellings on the second or seventh days after surgery (P > .05).

CONCLUSIONS

Pain, trismus, and swelling after lower third molar extraction, independent of surgical difficulty, were successfully controlled by sublingual ketorolac (10 mg 4 times daily) or sublingual piroxicam (20 mg once daily), and no significant differences were observed between the NSAIDs evaluated.

Comparison of oral versus sublingual piroxicam during postoperative pain management after lower third molar extraction

In this study, 53 patients received piroxicam, administered orally or sublingually, after undergoing removal of symmetrically positioned lower third molars, during two separate appointments. This study used a randomized, blind, cross-over protocol. Objective and subjective parameters were recorded for comparison of postoperative results for 7 days after surgery. Patients treated with oral or sublingual piroxicam reported low postoperative pain scores. The patients who received piroxicam orally took a similar average amount of analgesic rescue medication compared with patients who received piroxicam sublingually (p>0.05). Patients exhibited similar values for mouth opening measured just before surgery and immediately following suture removal 7 days later (p>0.05), and showed no significant differences between routes of piroxicam administration for swelling control during the second or seventh postoperative days (p>0.05). In summary, pain, trismus and swelling after lower third molar extraction, independent of surgical difficulty, could be controlled by piroxicam 20mg administered orally or sublingually and no significant differences were observed between the route of delivery used in this study.

Efficacy and safety of combined piroxicam, dexamethasone, orphenadrine, and cyanocobalamin treatment in mandibular molar surgery

Third molar extraction is a common procedure frequently accompanied by moderate or severe pain, and involves sufficient numbers of patients to make studies relatively easy to perform. The aim of the present study was to determine the efficacy and safety of the therapeutic combination of 10 mg piroxicam, 1 mg dexamethasone, 35 mg orphenadrine citrate, and 2.5 mg cyanocobalamin (Rheumazin) when compared with 20 mg piroxicam alone (Feldene) in mandibular third molar surgery. Eighty patients scheduled for removal of the third molar were included in this randomized and double-blind study. They received (vo) Rheumazin or Feldene 30 min after tooth extraction and once daily for 4 consecutive days. Pain was determined by a visual analogue scale and by the need for escape analgesia (paracetamol). Facial swelling was evaluated with a measuring tape and adverse effects and patient satisfaction were recorded. There was no statistically significant difference in facial swelling between Rheumazin and Feldene (control group). Both drugs were equally effective in the control of pain, with Rheumazin displaying less adverse effects than Feldene. Therefore, Rheumazin appears to provide a better risk/benefit ratio in the mandibular molar surgery. Since the side effects resulting from nonsteroidal anti-inflammatory drug administration are a severe limitation to the routine use of these drugs in clinical practice, our results suggest that Rheumazin can be a good choice for third molar removal treatment.

Over-the-counter analgesics: a toxicology perspective

The decision to use any analgesic is a balance of benefit and risk. In the case of analgesics, it is important to balance the therapeutic benefit against both the risk in therapeutic use and the risk (and ease of treatment) in overdose. Paracetamol in therapeutic dose carries little risk of adverse events. Less than 0.1% of the estimated 30 million paracetamol users in the United Kingdom attend hospital with a paracetamol overdose each year, and approximately 200 people die, most of whom presented late or did not receive antidote, N-acetylcysteine, within 12 hours. Nonsteriodal anti-inflammatory drugs (NSAIDs) have greater adverse effects in therapeutic use than paracetamol but also have a lower incidence of severe features or death in overdose. There is no antidote available for NSAID poisoning. Aspirin carries both significant adverse effects in therapeutic dose and a substantial risk in overdose, for which there is no antidote. Its risk-benefit profile is probably the poorest of all analgesics currently available over-the-counter (OTC); this is reflected in current trends both in analgesic use and overdose figures. Although a number of options to reduce deaths from poisoning by OTC analgesics have been considered, few are practical, and all must take account of the public health benefits provided by these drugs. A perspective should be retained that the vast majority of the population in Australia, the United States, the United Kingdom, and Denmark derive therapeutic benefit from OTC analgesics and do not take them in overdose. The majority of those who do take overdoses come to little or no harm. Management of serious poisoning by paracetamol, aspirin, or NSAIDs remains a medical challenge.

Treatment of fever in childhood

Although the need for routine antipyretic therapy in children has often been questioned, there are no data to contra-indicate this. Not all fevers need to be treated but many physicians do so to relieve parental concern. The most commonly used antipyretic drugs are acetylsalicylic acid (ASA), paracetamol (acetaminophen) and dipyrone (metamizol). Paracetamol and ASA have been extensively evaluated but there are few clinical trials on dipyrone. In the last decade a strong statistical association has been observed between salicylates and Reye syndrome. Paracetamol is the most common cause of acute hepatic failure. Dipyrone has been associated with agranulocytosis. In the light of these findings the extensive use of antipyretics drugs has been seriously questioned.

Transport management of the patient with acute poisoning

Poisoning in children is a common clinical problem encountered by pediatricians, general practitioners, and emergency room physicians. Poisoning in children less than 5 years of age is usually accidental, whereas, in young adults, any disparity between expected history and clinical findings should suggest poisoning. It is imperative that the treating physician expeditiously recognize, begin treating, and plan to transfer, when indicated, by specialized pediatric transport team the critically ill poisoned child to a tertiary care facility.

Tenoxicam. An update of its pharmacology and therapeutic efficacy in rheumatic diseases

Tenoxicam administered orally, rectally or parenterally is an effective analgesic and anti-inflammatory agent for the symptomatic treatment of rheumatoid arthritis, osteoarthritis, ankylosing spondylitis and various rheumatic conditions such as tendinitis, bursitis, sciatica, back pain and gouty arthritis. In clinical trials its efficacy is at least equivalent to that of other NSAIDs and it is at least as well tolerated as piroxicam and probably better tolerated than diclofenac, indomethacin and ketoprofen. Compared with many other NSAIDs, tenoxicam offers certain advantages in that it is conveniently administered once daily and dosage adjustment is not required in the elderly or in patients with renal or hepatic impairment.

Toxic effects of nonsteroidal anti-inflammatory drugs in overdose. An overview of recent evidence on clinical effects and dose-response relationships

Nonsalicylate, nonsteroidal anti-inflammatory drugs (NSAIDs) can be divided into 4 chemical classes: acetic acids, fenamic acids, oxicams and propionic acids. Most NSAID overdoses result in a benign outcome. Of 50,614 exposures reported to poison centres in the United States in a 2-year period, 131 (0.26%) had a major outcome, with 10 deaths. Despite the generally mild effects reported in large patient series, isolated case reports have documented serious toxicity, such as seizures, hypotension, apnoea, coma and renal failure. The majority of these consequences occur after ingestion of substantial quantities by adults attempting suicide. Rarely, with ibuprofen and piroxicam, children who ingest small amounts in accidental exposure develop serious toxicity. Typical signs and symptoms of NSAID overdose include nausea, vomiting, headache, drowsiness, blurred vision and dizziness. Seizures are rarely documented across all NSAID classes, with the exception of mefenamic acid (where seizures occur in over one-third of cases), or following massive ingestion of other agents. Drugs in the propionic acid group have produced metabolic acidosis, respiratory depression and coma in severe cases. Ibuprofen is the agent with the most published data on overdose, probably because it is available without a prescription in many countries. Symptoms are unlikely after ingestion of 100 mg/kg or less, and are usually not life-threatening unless more than 400 mg/kg is ingested. There is some relationship between plasma concentrations and the potential for development of symptoms, but plasma concentrations have no impact on treatment decisions. Treatment of NSAID overdose is entirely supportive. Recent trends in emergency department procedures regarding gastric decontamination are evolving towards the recommended administration of activated charcoal without gastric emptying in patients presenting more than 1 hour after ingestion, although gastric lavage, followed by administration of activated charcoal, may be advisable in patients who present earlier. Home administration of syrup of ipecac is still recommended if treatment is given shortly after ingestion, with a few exceptions: for example, ipecac is contraindicated after ingestion of mefenamic acid or ibuprofen in amounts greater than 400 mg/kg. Urine alkalinisation and diuresis have been recommended to enhance the elimination of NSAIDs, based on a pKa in the range of 3 to 5. However, because the drugs are universally highly protein bound, with little unchanged renal excretion, this technique is not likely to be beneficial. Haemodialysis is also unlikely to enhance elimination, but may be required if oliguric renal failure develops. Multiple dose activated charcoal may be useful in enhancing elimination of NSAIDs with long half-lives, such as piroxicam and sulindac.

Plasma and cerebrospinal fluid concentrations of indomethacin in humans. Relationship to analgesic activity

Plasma and cerebrospinal fluid (CSF) concentrations of indomethacin have been determined in 52 patients hospitalized for nerve-root compression pain. Samples of blood and CSF were collected at the same time in each subject, 0.5 to 12 h after a single intramuscular injection of 50 mg indomethacin. Analgesic effect was assessed by the absolute and percentage variation in Huskisson's visual analogue scale between dosing and sampling. According to its high lipid solubility, indomethacin rapidly crossed the blood-brain barrier, being detected in CSF 0.5 h after administration. After attainment of equilibrium within 2 h, the CSF level exceeded the free plasma level. Since the drug was extensively bound to serum albumin (99.7 +/- 0.1%), this phenomenon may represent a slight degree of binding of indomethacin in CSF. The analgesic activity was not related to either the plasma or CSF concentration of indomethacin.

Clinical pharmacology and use of nonsteroidal anti-inflammatory drugs

This review informs clinicians about current clinical usage and pharmacokinetics of newer NSAIDs and aspirin. To understand the effects of these drugs, a review of prostaglandin synthesis and actions is provided.