Repeated-dose

CONSTIPATION The nurse checks the bowel elimination pattern daily because constipation can occur with repeated doses of a narcotic. The nurse keeps a daily record of bowel movements and informs the primary health care provider if constipation appears to be a problem. Most patients should begin taking a stool softener or laxative with the initial dose of a narcotic analgesic. Many patients need to continue taking a laxative as long as the narcotic analgesic is taken. If the patient is constipated despite the use of a stool softener, the primary health care provider may prescribe an enema or another means of relieving constipation. 

The effects of some narcotics may last longer than the effects of naloxone. A repeat dose of naloxone may be ordered by the primary health care provider if results obtained from the initial dose are unsatisfactory. The duration of close patient observation depends on the patient s response to the administration of the narcotic antagonist. 

S3B Pharmacokinetics Guidance for Repeated Dose Tissue Distribution Studies Toxicity Testing... 

GL31 Safety Repeat-dose toxicity test Studies to evaluate the safety of residues of veterinary drugs in human food Repeat-dose toxidly testing... 

In conclusion, the obtained results suggest that the studied compounds differ from the point of view of acute hepatotoxicity. Only 2 and 2 after a single dose result in equal hepatotoxicity, as found previously for monobromo-benzene. The results obtained in part of experiments in which repeated doses were used, suggest the porphyrogenic properties of the compounds. This requires, however, an extended investigation with more specific indicators of such properties. 

Large or quickly repeating doses over a period of hours can led to extreme anxiety, paranoia and even hallucinations. These effects usually disappear as the drug is eliminated from the body. The after-effects of cocaine and crack use may include fatigue and depression as people come down from the high. Excessive doses can cause death from respiratory or heart failure but this is rare. 

In this special case when the time between dosings is equal to the half-life time of the drug, we can deduce that the minimum (steady-state) plasma concentration with repeated dosing is equal to the peak concentration, obtained from a single dose. Under this condition, the corresponding maximum (steady-state) concentration is twice as much as the minimum one. 

Tachyphylaxis develops with repeat doses. Activity may return after a 3-d drug-free period... 

Monitor electrocardiogram continuously in patients with cardiac abnormalities until serum potassium levels drop below 5 mEq/L (5 mmol/L) or cardiac abnormalities resolve. Evaluate serum potassium and glucose levels within 1 hour in patients who receive insulin and dextrose therapy. Evaluate serum potassium levels within 2 to 4 hours after treatment with SPS or diuretics. Repeat doses of diuretics or SPS if necessary until serum potassium levels fall below 5 mEq/L (5 mmol/L). Monitor blood pressure and serum potassium levels in 1 week in patients who receive fludrocortisone. 

Desmopressin (DDAVP) increases the release of factor VIII (von Willebrand factor) from endothelial tissue in the vessel wall. Bleeding time is promptly reduced, within 1 hour of administration, and is sustained for 4 to 8 hours.42 Doses used for uremic bleeding are 0.3 to 0.4 mcg/kg intravenously over 20 to 30 minutes, 0.3 mcg/kg subcutaneously, or 2 to 3 mcg/kg intranasally. Repeated doses can cause tachyphylaxis by... 

Diazepam Being extremely lipophilic, diazepam penetrates quickly into the CNS, but can rapidly redistribute into body fat and muscle. This results in a faster decline in CNS levels and early recurrence of seizures. It is dosed at 5 to 10 mg (or 0.15 mg/kg) and infused no faster than 5 mg/minute. Repeated doses can be given every 5 minutes until seizure activity stops or toxicities are seen (e.g., respiratory depression). Diazepam can also be administered as a rectal suppository, making it possible for non-medical personnel to provide rapid therapy for seizures that develop at home or in public areas.11 The adult dose is 10 mg given rectally and this dose may be repeated once if necessary. Diazepam is erratically absorbed via the intramuscular route therefore, IM administration is not recommended. 

Severe pain should be treated with an opioid such as morphine, hydromorphone, methadone, or fentanyl. Moderate pain can be treated effectively in most cases with a weak opioid such as codeine or hydrocodone, usually in combination with acetaminophen. Meperidine should be avoided owing to its relatively short analgesic effect and its toxic metabolite, normeperidine. Normeperidine may accumulate with repeated dosing and can lead to central nervous system side effects including seizures. 

Guidelines suggest that if an operation exceeds two half-lives of the selected antimicrobial, then another dose should be administered.1 Repeat dosing has been shown to lower rates of SSI. For example, cefazolin has a half-life of about 2 hours, thus... 

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