Ординатура / Офтальмология / Английские материалы / Drugs in Ophthalmlogy_Fong, Law, Schmidt-Erfurth_2006

Valganciclovir

207

monitoring for cytopenias may be warranted in patients with

Contraindications

renal impairment.

In patients with hypersensitivity to the product or any of its

components or to ganciclovir. Should not be administered if

the absolute neutrophil count is less than 500 cells/µl, plate-

let count is less than 25,000/µl, or hemoglobin is less than

8 g/dl. Should not be prescribed to patients receiving he-

modialysis; for patients on hemodialysis (CrCl <10 ml/min), a

Warnings

dose recommendation cannot be given.

Clinical toxicity of Valcyte, which is metabolized to ganciclo-

vir, includes granulocytopenia, anemia, and thrombocytope-

nia. In animal studies, ganciclovir was carcinogenic, terato-

genic, and caused aspermatogenesis. Valcyte tablets should,

therefore, be used with caution in patients with preexisting

cytopenias or who have received or who are receiving my-

elosuppressive drugs or irradiation. Should be considered a

potential teratogen and carcinogen in humans with the po-

tential to cause birth defects and cancers. Women of childbe-

aring potential should be advised to use effective contracep-

tion during treatment. Similarly, men should be advised to

practice barrier contraception during, and for at least 90 days

following, treatment. Not indicated for use in liver transplant

patients. In liver transplant patients, there was a significantly

higher incidence of tissue-invasive CMV disease in the Valcy-

Adverse Reactions

te-treated group compared with the oral ganciclovir group.

Valganciclovir, a prodrug of ganciclovir, is rapidly conver-

ted to ganciclovir after oral administration. Adverse events

known to be associated with ganciclovir usage can therefore

Pregnancy Category

be expected to occur.

C.

Drug Interactions

Because the drug is rapidly and extensively converted to

ganciclovir, interactions associated with ganciclovir will be

expected. Zidovudine and valganciclovir each have the po-

tential to cause neutropenia and anemia. Some patients may

not tolerate concomitant therapy at full dosage. Patients ta-

king probenecid concomitantly should be monitored for evi-

dence of ganciclovir toxicity. Patients with renal impairment

on concomitant mycophenolate mofetil should be monito-

red carefully, as levels of metabolites of both drugs may in-

crease. Patients on concomitant didanosine should be closely

monitored for didanosine toxicity.

Verteporfin

209

been reported. Miscellaneous: infrequently; anaphylaxis, drug

fever, chills, nausea, eosinophilia, rashes (including exfoliative

dermatitis), Stevens–Johnson syndrome, toxic epidermal ne-

Pregnancy Category

crolysis, and rare cases of vasculitis have been reported.

B.

Drug Interactions

Excreted in human milk based on information obtained with

i.v. administration. However, systemic absorption is very low

following oral administration. It is not known whether oral

vancomycin is excreted in human milk, as no studies follo-

wing oral administration have been done. Safety and effec-

tiveness in pediatric patients have not been established.

Brand Name

Visudyne.

Class of Drug

Light sensitizer, light-activated; used in photodynamic thera-

Indications

py.

For the treatment of patients with predominantly classic sub-

foveal choroidal neovascularization due to AMD, pathologic

myopia, or presumed ocular histoplasmosis (for other forms

Dosage Form

of CNV, just experimental).

Solution for i.v. injection: each milliliter contains 2 mg verte-

Dose

porfin.

Reconstitute each vial with 7 ml sterile water for injection to

provide 7.5 ml containing 2 mg/ml. Reconstituted Visudyne

must be protected from light and used within 4 h. It is recom-

mended that reconstituted Visudyne be inspected visually

for particulate matter and discoloration prior to administrati-

on. The volume of reconstituted Visudyne required to achieve

the desired dose of 6 mg/m2 body surface area is withdrawn

from the vial and diluted with 5% dextrose for injection to

a total infusion volume of 30 ml. The full infusion volume is

administered i.v. over 10 min at a rate of 3 ml/min using an

Contraindications

appropriate syringe pump and in-line filter.

In patients with porphyria or a known hypersensitivity to the

product or any of its components. Should be considered care-

fully in patients with moderate to severe hepatic impairment

or biliary obstruction since there is no clinical experience in

Warnings

such patients.

Following injection, care should be taken to avoid exposure

of skin or eyes to direct sunlight or bright indoor light for 5

days. In the event of extravasation during infusion, the extra-

vasation area must be thoroughly protected from direct light

until swelling and discoloration have faded in order to pre-

vent the occurrence of a local burn, which could be severe. If

Vitamins with Minerals

211

sumption may be associated with an increased risk of adver-

se effects. There is also concern that long-term use of vita-

min A in high does (>5,000 IU per day) can increase the risk

of osteoporosis in women;beta-carotene may cause orange

stools and cause diarrhea or loose stools at onset of therapy

that tend to resolve with continued use. Vitamin C and E may

interfere with effectiveness of statin therapy. Elevated levels

of zinc have been associated with neurodegeneration in ani-

mal models, elevation of glycosylated hemoglobin levels in

type I diabetics, decreased glucose tolerance in type II diabe-

tes, and elevated serum zinc levels may be found in patients

with Alzheimer’s disease. Necrotizing enterocolitis may occur

when large doses of vitamin E are given. Withdrawal of chro-

nic, high levels of vitamin C may lead to rebound deficiency

due to increased clearance; probably requires taper or redu-

ced dose at US MDR; prolonged high doses may cause renal

Pregnancy Category

calculi, especially in diabetics.

Taking large amounts of a dietary supplements in pregnancy

may be harmful to the mother and/or fetus and should be

avoided.

Brand Name

ICaps.

Dosage Form

Vitamin A 14,320 IU 286%, vitamin C 226 mg 376%, vitamin E

Contraindications

200 IU 666%, zinc 34.8 mg 232%, copper 0.8 mg 40%.

Most significant: Wilson‘s disease. Significant: biliary tract

disorder, copper deficiency. Possibly significant: liver di-

Adverse Reactions

sease.

Most frequent: carotenodermia. Rare: abdominal pain with

cramps, arthralgia, diarrhea, dizziness, dyspepsia, ecchymo-

sis, gastrointestinal disorder, leukopenia, nausea, neutrope-

nia, sideroblastic anemia.

Brand Name

Ocuvite.

Dosage Form

Vitamin A 1,000 IU 20% vitamin C 200 mg 330%, vitamin E

60 IU 200%, zinc 40 mg 270%, selenium 55 mcg 80%, copper

Adverse Reactions

2 mg 100%, lutein 2 mg N/A.

Most frequent: carotenodermia. Rare: arthralgia, diarrhea, diz-

ziness, ecchymosis.

Brand Name

Ocuvite Extra.

Dosage Form

Vitamin A 1,000 IU 20%, vitamin C 300 mg 500%, vitamin E

100 IU 330%, riboflavin 3 mg 180%, niacinamide 40 mg 200%,

zinc 40 mg 270%, selenium 55 mcg 80%, copper 2 mg 100%,

manganese 5 mg 250%, L-glutathione 5 mg N/A, lutein 2 mg

Adverse Reactions

N/A.

Less frequent: nausea, vomiting.

Brand Name

Ocuvite PreserVision.

Dosage Form

Beta-carotene 17.2 mg N/A, vitamin C 452 mg 753%, vitamin

E 268 mg 2,680%, zinc 69.6 mg 464%, copper 1.6 mg N/A.

Vitamins with Minerals

213

Contraindications

Documented hypersensitivity.

Warnings

Eliminated via the bile; accumulates in patients with severe

Adverse Reactions

liver dysfunction and/or biliary tract obstruction.

Elevated blood concentration and neurotoxicity.

Pregnancy Category

C.

Brand Name

Niacinamide.

Indications

Coenzyme or cosubstrate in many biological reduction or

Dosage Form

oxidation reactions; thus required for energy metabolism.

Oral and injectable.

Contraindications

In insulin-dependent diabetes, aggravates blood sugar pro-

Adverse Reactions

blems.

With injection only: skin rash or itching; wheezing. With prolon-

ged use of extended-release niacin: darkening of urine; light-

gray-colored stools; loss of appetite; severe stomach pain;

yellow eyes or skin. Less common with niacin only: feeling of

warmth; flushing or redness of skin, especially on face and

neck; headache. With high doses: Diarrhea; dizziness or faint-

ness; dryness of skin; fever; frequent urination; itching of skin;

joint pain; muscle aching or cramping; nausea or vomiting;

side, lower back, or stomach pain; swelling of feet or lower

legs; unusual thirst; unusual tiredness or weakness; unusually

Pregnancy Category

fast, slow, or irregular heartbeat.

C.

Brand Name

Riboflavin (vitamin B2).

Indications

Coenzyme in numerous redox reactions.

Dosage Form

Oral.

Contraindications

In patients with known hypersensitivity to the product.

Adverse Reactions

May cause urine to become yellow-orange color; this effect is

harmless.

Brand Name

Selenium.

Indications

Defense against oxidative stress and regulation of thyroid

hormone action; reduction and oxidation status of vitamin C

Dosage Form

and other molecules.

Oral: as mineral supplements. Injectable: as trace minerals for

Warnings

TRN supplement.

Eliminated inurine and feces; may be adjusted, reduced, or

omitted in renal dysfunction and/or gastrointestinal mal-

function. In patients receiving blood transfusions, contribu-

tion from such transfusions should also be considered. Fre-

quent selenium plasma level determinations are suggested

as a guideline. Presence in placenta and umbilical cord blood

has been reported in humans.

Adverse Reactions

Hair and nail brittleness and loss.

Pregnancy Category

C.

Drug Interactions

In animals, has been reported to enhance theaction of vitamin

E and decrease toxicity of mercury, cadmium, and arsenic.

Voriconazole

215

Brand Name

VFEND: injection, tablets, oral suspension.

Class of Drug

Antifungal.

Indications

Invasive aspergillosis: in clinical trials, the majority of isolates

recovered were Aspergillus fumigatus. Small number of cases

of culture-proven disease due to Aspergillus spp. other than

A. fumigatus. Esophageal candidiasis; serious fungal infections

caused by Scedosporium apiospermum (asexual form of Pseu-

dallescheria boydii) and Fusarium spp., including Fusarium so-

Dosage Form

lani, in patients intolerant of, or refractory to, other therapy.

Injection, oral tablets, oral suspension.

Dose

Loading dose regimen: 6 mg/kg i.v. every 12 h (for the first

24 h). Maintenance dose: IV—4 mg/kg every 12 h. Oral*—

200 mg every 12 h. (*Patients who weigh 40 kg or more

should receive an oral maintenance dose of 200 mg every

12 h. Adult patients who weigh less than 40 kg should recei-

ve an oral maintenance dose of 100 mg every 12 h. If patient

response is inadequate, the oral maintenance dose may be

increased from 200 mg every 12 h to 300 mg every 12 h. For

adult patients weighing less than 40 kg, the oral maintenance

dose may be increased from 100 mg every 12 h to 150 mg

every 12 h. If patients are unable to tolerate treatment, re-

duce the i.v. maintenance dose to 3 mg/kg every 12 h and

the oral maintenance dose by 50 mg steps to a minimum of

200 mg every 12 h; or to 100 mg every 12 h for adult patients

Contraindications

weighing less than 40 kg.)

Coadministration with: CYP3A4 substrates terfenadine, aste-

mizole, cisapride, pimozide, or quinidine, as increased plas-

ma concentrations of these drugs can lead to QT prolonga-

tion and rare occurrences of torsade de pointes; sirolimus, as

VFEND significantly increases sirolimus concentrations in

healthy subjects; rifampin, carbamazepine, and long-acting