Drug overdoses aspirin

N-Acetylcysteine is useful in which of the following drug overdoses a aspirin... 

Drugs can interact with other drugs. For example, some drugs used for diabetes are bound by plasma protein in the blood supply and are therefore not free to react with receptors. However, they can be displaced from the plasma protein by aspirin and this can lead to a drug overdose. A similar phenomenon is observed between anticoagulents and aspirin. 

Recommendations for sodium bicarbonate vary (from class 1 to class in) depending on the clinical situation. Sodium bicarbonate use is acceptable for patients with known, preexisting hyperkalemia (class 1), preexisting bicarbonate-responsive acidosis (class 11a), overdoses of tricychc antidepressants (class 11a), and to aUcalinize the urine in aspirin and other drug overdoses (class 11a). In addition, sodium bicarbonate may be of benefit in intubated and ventilated patients with along arrest interval (class 11b). Sodium bicarbonate may be harmful in hypercarbic acidosis, and patients with this condition should not receive it (class IH). 

Answer E. Back to basic principles. Zero-order elimination means that plasma levels of a drug decrease linearly with time. This occurs with ASA at toxic doses, with phenytoin at high therapeutic doses, and with ethanol at all doses. Enzymes that metabolize ASA are saturated at high plasma levels —> constant rate of metabolism = zero-order kinetics. Remember that application of the Henderson-Hasselbalch principle can be important in drug overdose situations. In the case of aspirin, a weak acid, urinary alkalinization favors ionization of the drug —>4 tubular reabsorption —>T renal elimination. 

Accidental poisonings are common with both aspirin and ibuprofen, two OTC drugs available in tasty chewable tablets. In cases of overdose, aspirin is more likely than ibuprofen to cause... 

Example In an overdose case where evidence was available for the ingestion of Percodan (a mixture of several common drugs) the isobutane-CI mass spectrum of the gastric extract was obtained (Fig. 7.8). [29] All drugs give rise to an [Mh-H] ion. Due to the low exothermicity of protonation by the tert-C Hi) ion, most [Mh-H]" ions do not show fragmentation. Solely that of aspirin shows intense... 

This drug is relatively free from serious side effects. Problems with salicylate intoxication may occur during overdose or in people who are sensitive to aspirin and other salicylates. 

Codeine Phosphate The presence of aspirin along with codeine, even at a low moisture level, leads to acetylation of codeine phosphate in solid dose forms and is incompatible.36 Codeine sulfate solutions are more stable than phosphate salts.37 Drug dependence and withdrawal resemble that of opioid analgesics. Overdose causes acute intoxication in children, as accidental or deliberate ingestion of cough preparations containing codeine.38... 

Apart from the symptoms, how would a doctor know that someone had taken an overdose of aspirin As already described, there are simple tests that can be done on urine to find out if someone suspected of an overdose has taken any of the common drugs. After the drug taken is known, it is important to measure the level of the drug in the blood to find out the likely dose and therefore the necessary treatment (see... 

It may be that limiting access to one type of drug simply increases the incidence of overdose with other potentially more dangerous medicines. If that is so, unless the availability of other medications is also controlled, the removal of one readily available medication, such as paracetamol, could lead to an increase in the use of other compounds with similar or even greater toxicity (for example aspirin, ibuprofen). 

Antihistamines are present in prescription and nonprescription forms, alone or in combination with analgesics, such as aspirin and acetaminophen. In instances of overdose, a urine drug screen that detects sahcylate, acetaminophen, and the antihistamines is helpful, especially when the source of intoxication is unknown. The detection of either analgesic in the urine of a symptomatic patient should lead to their quantitation in serum to assess their potential toxicity (see sections on Salicylate and Acetaminophen). Quantitation of antihistamines in serum is not useful, because there is a poor correlation between dose, drug level, and degree of toxicity. 

Administration of sodium bicarbonate increases the alkalinity of the tubular filtrate therefore acidic drugs, for example aspirin and barbiturates become ionized and cannot diffuse back from the tubules to the plasma. Hence their rate of elimination is increased. This may be useful in the event of an overdose. 

Care needs to be taken when combining naproxen with other medications. Known adverse drug interactions can occur with aspirin, methotrexate, ACE inhibitors (for high blood pressure), furosemide, lithium, and warfarin (a blood thinner). An overdose of naproxen may cause dizziness, drowsiness, and gastrointestinal problems. High blood pressure, kidney failure, and coma may occur, but are rare. 

Aspirin, sympathomimetics, agents with muscarinic blocking actions, and drugs that cause muscle rigidity or seizures are all likely to cause hyperthermia at toxic doses. Hypothermia is more typical of overdoses with opioids or sedative-hypnotics. The answer is (C). 

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