Chemistry

Beta Switch Program

The Beta Switch Weight Loss Program by Sue Heintze

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The basic structure of steroids consists of a 21-carbon steroid molecule (Fig. 2). The major biologically active glucocorticoid is cortisol (hydrocortisone). Steroids with an 11-ketone group (cortisone and prednisone) are biologically inactive until reduced to a 11-hydroxial compound (hydrocortisone and prednisolone, respectively) (18). Therefore, preparations such as cortisone and prednisone, which require bioactivation in the liver, can only be used systemically. Hence, cortisone and prednisone are not useful for selective injections. For selective injections, biologically active hydroxicorticoid preparations such as methylprednisolone, triamcinolone, or other steriods must be used (Table 2) (3,5-7,19).

FIGURE 2 Chemical structure of selected steroids used for selective injections.
TABLE 2 Comparative Potencies and Duration of Action of Selected Steroids Used for Selective Injections

Anti-inflammatory

Mineralocorticoid

Duration

Nonproprietary name

Drug

potency (cortisol=1)

potency (cortisol = 1)

of action

(trade name)a

Hydrocortisone

1

1

S

Hydrocortisone sodium phosphate

(hydrocortone phosphate),

hydrocortisone sodium

succinate (Solucortef,

A-Hydrocort) (7)

Methylpredni-

5

0.5

I

Methylprednisolone acetate

solone

(Depo-Medrol) (19,20)

Triamcinolone

5

0

I

Triamcinolone diacetate

(Kenacort) (5)

Cortivazol

I

Cortivazol (Altim) (3,21)

Betamethasone

25

0

L

Betamethasone sodium phosphate

(Celestone Phosphate),

Betamethasone sodium

phosphate and acetate

(Celestone Soluspan) (2,6)

aRefers to reference.

Abbreviations: S, short (i.e., 8-12 hour biological halt-lite); I, Intermediate (I.e., 12-36 hour biological half-life); L, long (I.e., 63-72 hour biological half-life).

aRefers to reference.

Abbreviations: S, short (i.e., 8-12 hour biological halt-lite); I, Intermediate (I.e., 12-36 hour biological half-life); L, long (I.e., 63-72 hour biological half-life).

Steroids are grouped according to their relative potency of Na+ retention, effects on carbohydrate metabolism (i.e., hepatic deposition of glycogen and gluconeogenesis), and anti-inflammatory effects. In general, the potencies of steroids, as judged by their ability to sustain life in the adrenalectomized animal, closely parallel those determined for Na+ retention. Potencies based on effects on glucose metabolism closely parallel those for anti-inflammatory effects. The effects on Na+ retention and carbohydrate/anti-inflammatory effects are not closely related. Based on these differential potencies, the steroids are classically divided into mineralo-corticoids and glucocorticoids.

For selective injections, steroid preparations of various potencies, as compared to the effect of prednisone, are available (Table 2). The crystalloid constitution of all these drugs is important for local action. Alteration in the molecular structure has yielded preparations with useful differences in potency, mineralocorticoid activity, and pharmacokinetic profiles. Although some investigators believe that the more potent preparations are also more efficacious, the clinical evidence for this is only moderate, and comparative studies of different preparations are not reported. Many clinicians have settled on a preparation that seems to have, in their opinion, good benefit and few side effects. Some prefer, for example, a preparation of a short-acting solution and long-acting suspension of betamethasone (Celestone Soluspane®). They believe that the solution works rapidly and prevents the possibility of postinjection flare. Betamethasone has the longest biological half-life and, therefore, the longest duration in suppressing inflammation.

Mixing the steroid suspension with a local anesthetic avoids the injection of high concentrations, which may produce soft-tissue atrophy or pericapsular calcification. However, one has to be concerned about the compatibility of the two preparations, in particular, when the steroid is mixed with local anesthetics containing preservatives. This may result in flocculation of the steroid.

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