Twice-a-day dose

Elecainide is weU absorbed and 90% of the po dose is bioavailable. Binding to plasma protein is only 40% and peak plasma concentrations are attained in about 1—6 h. Three to five days may be requited to attain steady-state plasma concentrations when multiple doses are used. Therapeutic plasma concentrations are 0.2—1.0 lg/mL. Elecainide has an elimination half-life of 12—27 h, allowing twice a day dosing. The plasma half-life is increased in patients with renal failure or low cardiac outputs. About 70% of the flecainide in plasma is metabolized by the Hver to two principal metaboUtes. The antiarrhythmic potency of the meta-O-dealkylated metaboUte and the meta-O-dealkylated lactam, relative to that of flecainide is 50 and 10%, respectively. The plasma concentrations of the two metaboUtes relative to that of flecainide are 3—25%. Elecainide is mainly excreted by the kidneys, 30% unchanged, the rest as metaboUtes or conjugates about 5% is excreted in the feces (1,2). 

Take the drug early in the morning (once-a-day dosage) unless directed otherwise to minimize the effects on nighttime sleep. Twice-a-day dosing should be administered early in the morning (eg,... 

HISTAMINE H2 ANTAGONISTS. The nurse administers ranitidine and oral cimetidine before or with meals and at bedtime Nizatidine and famotidine are given at bedtime or, if twice-a-day dosing is prescribed, in the morning and at bedtime. These drugp are usually given concurrently with an antacid to relieve the pain. In certain situations or disorders, cimetidine and ranitidine may also be given by intermittent IV infusion or direct IV injection. 

As noted in the patent for this system, pulsatile systems are expected to have numerous applications in drug delivery, including site-specific delivery in the GI tract and bid (twice-a-day) dosing of two pulsatile systems that simulates qid (four times a day) dosing of immediately available products. The latter concept is expected to have a particular advantage for those drugs that have high first-pass metabolism. 

Although some patients, especially those on monotherapy, can be maintained on twice-a-day dosing, others may require more frequent administration, especially children. Larger doses can be given at bedtime. Dose increases can be made every 2 to 3 weeks. 

The sustained- and controlled-release dosage forms allow for twice-a-day dosing. The sustained-release capsule can be opened and sprinkled on food. 

Oral The peak effects of single oral doses occur within 2 to 4 hours and lasts 8 to 12 hours. The maximum, steady-state BP response upon oral, twice-a-day dosing occurs within 24 to 72 hours. 

Disadvantages of nefazodone include the need for a twice-a-day dosing schedule and dose adjustment. Work is under way to develop a once-a-day sustained release version of nefazodone. The fact that nefazodone must be started at a lower than usually effective dose and then adjusted to an effective dose is a distinct disadvantage. That is made even more problematic because arguably more variability exists among patients in terms of the optimal dose of nefazodone as far as efficacy and tolerability than for virtually any other antidepressant. Finally, nefazodone produces substantial inhibition of CYP 3A3/4, leading to the potential for adverse pharmacokinetic interactions as well as possible unknown long-term consequences. 

Liquid i.v. Reduces fluctuations of plasma level compared to standard release. Tablets may be given twice a day Dose as tablets, twice a day No dosage adjustment. Given as slow i.v. bolus or infusion. Not to be mixed with other i.v. drugs in the same line... 

Doxycycline also requires only twice-a-day dosing and can be taken with foods, both of which enconrage patient compliance. 

Oral sulfasalazine is of proven value in patients with mild or moderately active ulcerative colitis, with response rates of60-80%. The usual dose is 4 g/day in four divided doses with food to avoid adverse effects, the dose is increased gradually from an initial dose of500 mg twice a day. Doses as high as 6 g/day can be used but cause an increased incidence of side effects. For patients with severe colitis, sulfasalazine is of less certain value, even though it is often added as an adjunct to... 

Suppressive therapy with Valtrex is once daily, every day. This is an advantage of Valtrex over other antiretroviral agents, which require twice-a-day dosing. 

An alternative to adjusting the dose of a drug is to decrease the frequency at which the normal dose is administered. For example, if a normal is dose is 250 mg four times a day (qid) or one tablet four times a day, then this can be reduced to three times a day or twice a day dosing. 

Dr. Michelakis believes We have now shown that DCA can be used in patients suffering from GBM... and was associated with... tumor regression and... has an overall good safety profile." DCA side effects were minimal on the four patients, and no apparent effects other than dose-dependent, reversible nondemyelinating, neurotoxicity that was minimal or absent at 6.25 mg/kg oral, twice-a-day dose. ... 

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