Epinephrine hydrochloride

FIG. 17 Chemical structures of (a) epinephrine hydrochloride, (b) dopamine hydrochloride, (c) isoproterenol hydrochloride, (d) phenylephrine hydrochloride, (e) tolazoline hydrochloride, (f) oxyprenolol hydrochloride, (g) alprenolol hydrochloride, and (h) propranolol hydrochloride. 

Epinephrine hydrochloride Mild to moderate stinging 2.5 1.5 Medium... 

Stablizers. Stabilizers are ingredients added to a formula to decrease the rate of decomposition of the active ingredients. Antioxidants are the principal stabilizers added to some ophthalmic solutions, primarily those containing epinephrine and other oxidizable drugs. Sodium bisulfite or metabisulfite are used in concentration up to 0.3% in epinephrine hydrochloride and bitartrate solutions. Epinephrine borate solutions have a pH range of 5.5 7.5 and offer a more difficult challenge to formulators who seek to prevent oxidation. Several patented antioxidant systems have been developed specifically for this compound. These consist of ascorbic acid and acetylcysteine, and sodium bisulfite and 8-hydroxyquinoline. Isoascorbic acid is also an effective antioxidant for this drug. Sodium thiosulfate is used with sodium sulfacetamide solutions. 

Fentanyl citrate—bupivacaine hydrochloride-epinephrine hydrochloride injection (100 mL)... 

Alpha- and beta-adrenergic agonists epinephrine bitartrate epinephrine hydrochloride, racemic... 

The pH value is not the sole contributing factor to discomfort of some ophthalmic solutions. It is possible to have a product with a low pH and little buffer capacity that is more comfortable than a similar product with a higher pH and a stronger buffer capacity. Epinephrine hydrochloride and dipivefrin hydrochloride solutions, used for treatment of glaucoma, have a pH of about 3, yet they have sufficiently acceptable comfort to have been used daily for many years. The same pH solution of epinephrine bitartrate has an intrinsically higher buffer capacity and will produce much more discomfort. 

Epinephrine is available as epinephrine hydrochloride and epinephryl borate solutions. The various salts of epinephrine produce equivalent lOP-lowering effects and adverse reactions. Patients with minor ocular irritation from one salt of epinephrine occasionally may benefit from use of another salt because of differences in pH of the commercial solutions. 

Larson, T.A. and Schilling, C.G. (1996) Stability of epinephrine hydrochloride in an extemporaneously compounded topical anaesthetic solution of lidocaine, racepinephrine and tetracaine, Am. J. Health-Syst. Pharm., 53, 659-662. 

EPINEPHRINE HYDROCHLORIDE (Adrenalin Chloride, AsthmaNefrin, Epifrin,... 

J-Form hydrochloride, CgH,ClNO, Arterenol. Crystals, mp 145.2-146,4. ( )f —40 (c - 6). Freely sol in water. Solns slowly oxidize under the influence of light and oxygen in a manner comparable to epinephrine hydrochloride. 

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