Corticosteroids timed administration

Topical intranasal decongestants (e.g., oxymetolazine, xylome-tolazine, phenylephrine, and naphazoline) are OTC options that provide prompt relief of nasal congestion. Nasal decongestants are dosed multiple times daily.15 Tachyphylaxis, rebound congestion, and rhinitis medicamentosa may occur with chronic use therefore, use should be limited to 3 to 5 days.8,12 These may be used 5 to 10 minutes before administration of intranasal corticosteroids in patients with blocked nasal passages.15... 

Hydrocortisone given parenterally is the corticosteroid of choice because of its combined glucocorticoid and mineralocorticoid activity. The starting dose is 100 mg IV by rapid infusion, followed by a continuous infusion or intermittent bolus of 100 to 200 mg every 24 hours. IV administration is continued for 24 to 48 hours. If the patient is stable at that time, oral hydrocortisone can be started at a dose of 50 mg every 8 hours for another 48 hours. A hydrocortisone taper is then initiated until the dosage is 30 to 50 mg/day in divided doses. 

The time of administration can also affect drug response e.g. INH and rifampicin (anti-tubercular drugs) are taken in early morning empty stomach. The corticosteroids when taken in morning as single dose cause less adrenal-pituitary suppression. 

The dosage should be kept as low as possible, and intermittent administration (eg, alternate-day) should be used when satisfactory therapeutic results can be obtained on this schedule. Even patients maintained on relatively low doses of corticosteroids may require supplementary therapy at times of stress, such as when surgical procedures are performed or intercurrent illness or accidents occur. 

The success of intravitreal implants, such as achieved with ganciclovir, has renewed interest in developing an intravitreal corticosteroid implant to further enhance the intravitreal route of administration, thus reducing the need for multiple injections. Bausch and Lomb and Control Delivery Systems have developed an intravitreal implant that can deliver the corticosteroid fluocinolone acetonide (Retrisert) to posterior eye tissue for up to 3 years. The implant, which was approved in 2005 by the U.S. Food and DrugAdministration (FDA), delivers 0.59 or 2.1 mg of fluocinolone acetonide. The long-term ocular side effects of this device are unknown at this time. 

Induction of ocular hypertension after corticosteroid administration depends on the specific drug, the dose, the route and frequency of administration, and the corticosteroid responsiveness of the patient. Generally, patients with elevated lOP are asymptomatic, so examination with applanation tonometry is the key to diagnosis. If the patient shows a steroid responsiveness, the onset of lOP elevations is not immediate but occurs after approximately 2 weeks of use. However, it can occur many weeks later, and this time to onset is generally longer for systemic steroids. In responsive patients the level of lOP rise with systemic steroids averages approximately 60% of that produced by topically applied steroids. 

The timing of corticosteroid administration has been pinpointed to interact with the diurnal rhythm of the hypothalamic-pituitary-adrenal axis in humans (Meibohm et al 1997). Dose timing has a pivotal effect on the safety profile and consequently the risk-benefit ratio of inhaled corticosteroids. In humans, maximum adrenal suppression occurs with the administration of aerosolized corticosteroids in the early morning hours, whereas endogenous cortisol production is least disrupted by administration in the afternoon. The circadian pattern results from the... 

There are three aerosolized corticosteroid preparatioias available in MDI formulation for administration to horses via the Equine AeroMask beclometasone dipropionate, fluticasone propionate and flunisolide (Table 16.2). In terms of the relative potency, fluticasone is more potent than beclometasone, which is more potent than flunisolide, which is equipotent to triamcinolone. Using dexamethasone as the standard (1.0), the relative glucocorticoid receptor affinity of the common corticosteroids is flunisolide 1.9, triamcinolone 2.0, beclometasone (active metabolite) 13.5 and fluticasone propionate 22.0 (Barnes et al 1998). The pulmonary residence time of the aerosolized corticosteroids is determined by the lipophilicity of each drug. Flunisolide has intermediate water solubility (lOmg/ml), simitar to... 

Meibohm B, Hochhaus G, Rohatoagi S et ai 1997 Dependency of cortisol suppression on the administration time of inhal corticosteroids. 

Time of Administration The presence or absence of food in the gastrointestinal tract, corticosteroid secretion rhythm, circadian cycle, urinary excretion pattern, fluid intake, and drug-metabolizing enzyme rhythms all can influence the effect of the medication. 

It Is less effective at controlling nasal symptoms than corticosteroids and has the disadvantage of requiring administration at least four times daily. However, it is safe and is suitable for children from 5 years of age. 

The management of preterm labor has centered on the use of tocolytic drugs. The goal of tocolytic therapy is to postpone delivery long enough to reduce the incidence of problems associated with prematurity. Tocolytics have not been shown to reduce the number of premature deliveries, but they may allow sufficient time for the administration of antenatal corticosteroids to improve pulmonary maturity and for transportation of the mother to a facility equipped to deal with high-risk deliveries. ... 

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