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Mydfrin Ophthalmic Solution Dosage

Generic name: Phenylephrine Hydrochloride 25mg in 1mL
Dosage form: ophthalmic solution

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Vasoconstriction and Pupil Dilation: MYDFRIN® phenylephrine hydrochloride ophthalmic solution 2.5% is especially useful when rapid and powerful dilation of the pupil without cycloplegia and reduction of congestion in the capillary bed are desired. A drop of a suitable topical anesthetic may be applied, followed in a few minutes by 1 drop of MYDFRIN phenylephrine hydrochloride ophthalmic solution 2.5% on the upper limbus. The anesthetic prevents stinging and consequent dilution of the solution by lacrimation. It may occasionally be necessary to repeat the instillation after one hour, again preceded by the use of the topical anesthetic.

Uveitis: Posterior Synechiae: MYDFRIN® phenylephrine hydrochloride ophthalmic solution 2.5% may be used in patients with uveitis when synechiae are present or may develop. The formation of synechiae may be prevented by the use of this solution and atropine or other cycloplegics to produce wide dilation of the pupil. For recently formed posterior synechiae one drop of MYDFRIN phenylephrine hydrochloride ophthalmic solution 2.5% may be applied to the upper surface of the cornea and be repeated as necessary, not to exceed three times. Treatment may be continued the following day, if necessary. Atropine sulfate and the application of hot compresses should also be used if indicated.

Glaucoma: MYDFRIN phenylephrine hydrochloride ophthalmic solution 2.5% may be used with miotics in patients with open angle glaucoma. It reduces the difficulties experienced by the patient because of the small field produced by miosis, and still it permits and often supports the effect of the miotic in lowering the intraocular pressure in open angle glaucoma. Hence, there may be marked improvement in visual acuity after using MYDFRIN phenylephrine hydrochloride ophthalmic solution 2.5% in conjunction with miotic drugs.

Surgery: When a short-acting mydriatic is needed for wide dilation of the pupil before intraocular surgery, MYDFRIN phenylephrine hydrochloride ophthalmic solution 2.5% may be applied topically from 30 to 60 minutes before the operation.

Refraction: MYDFRIN® phenylephrine hydrochloride ophthalmic solution 2.5% may be used effectively to increase mydriasis with homatropine hydrobromide, cyclopentolate hydrochloride, tropicamide hydrochloride and atropine sulfate.

FOR ADULTS
One drop of the preferred cycloplegic is placed in each eye, followed in 5 minutes by one drop of MYDFRIN phenylephrine hydrochloride ophthalmic solution 2.5%. Since adequate cycloplegia is achieved at different time intervals after the instillation of the necessary number of drops, different cycloplegics will require different waiting periods to achieve adequate cycloplegia.

FOR CHILDREN
For a “one application method,” MYDFRIN® phenylephrine hydrochloride ophthalmic solution 2.5% may be combined with one of the preferred rapid acting cycloplegics to produce adequate cycloplegia.

Ophthalmoscopic Examination: One drop of MYDFRIN phenylephrine hydrochloride ophthalmic solution 2.5% is placed in each eye. Sufficient mydriasis to permit examination is produced in 15 to 30 minutes. Dilation lasts from one to three hours.

Diagnostic Procedures: Provocative Test for Angle Closure Glaucoma: MYDFRIN phenylephrine hydrochloride ophthalmic solution 2.5% may be used cautiously as a provocative test when interval narrow angle closure glaucoma is suspected. Intraocular tension and gonioscopy are performed prior to and after dilation of the pupil with phenylephrine HCl. A “significant” intraocular pressure (IOP) rise combined with gonioscopic evidence of angle closure indicates an anterior segment anatomy capable of angle closure. A negative test does not rule this out. This pharmacologically induced angle closure glaucoma may not simulate real life conditions and other causes for transient elevations of IOP should be excluded.

Retinoscopy (Shadow Test): When dilation of the pupil without cycloplegic action is desired for retinoscopy, MYDFRIN® phenylephrine hydrochloride ophthalmic solution 2.5% may be used.

NOTE: Heavily pigmented irides may require larger doses in all of the above procedures.

Blanching Test: One or two drops of MYDFRIN phenylephrine hydrochloride ophthalmic solution 2.5% should be applied to the injected eye. After five minutes, examine for perilimbal blanching. If blanching occurs, the congestion is superficial and probably does not indicate iridocyclitis.

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