P H A R M A G R A M    

...an educational memo from your Pharmacy and Therapeutics Committee

March, 2004

 

Parenteral Prochlorperazine (Compazine®) Now Available:

For about 2 years the parenteral form of prochlorperazine has been unavailable due to material shortages and production problems. During this interim period the Pharmacy and Therapeutics Committee had authorized an auto-substitution to promethazine (Phenergan®). Since prochlorperazine injection is now available again, this auto-substitution will now be abandoned.

 

Linezolid (Zyvox®) Interactions Associated with Monoamine Oxidase Inhibition:

Linezolid is an oxazolidinone class antibiotic usually reserved for use in treating infections caused by vancomycin-resistant E faecium or methicillin-resistant S aureus. Linezolid is also a reversible, nonselective inhibitor of monoamine oxidase and therefore has the potential for interactions with adrenergic and serotonergic agents. Some individuals receiving linezolid may experience a reversible enhancement of the pressor response to indirect-acting sympathomimetic agents, vasopressor or dopaminergic agents. Initial doses of adrenergic agents, such as dopamine or epinephrine, should be reduced and titrated to achieve the desired response. Over the past 3 years there have been at least 7 reports in the literature and one documented case here at SFMC of serotonin syndrome associated with the concomitant use of linezolid and a serotonin reuptake inhibitor (i.e.citalopram (Celexa®), sertraline (Zoloft®), paroxetine (Paxil®), fluoxetine (Prozac®). Physicians should be alert to the possibility of signs and symptoms of serotonin syndrome (e.g. myoclonus, hyperreflexia, diaphoresis, shivering, tremor, diarrhea, incoordination hyperpyrexia, and cognitive dysfunction) in patients receiving such concomitant therapy.

 

Formulary Deletions and Autosubstitutions Approved:

Ø      Mumps, trichophyton and candida antigens were deleted from the Formulary. Mumps antigen is no longer available and the other agents are rarely used.

Ø      Oral ganciclovir (Cytovene®), used in the treatment of cytomegalovirus, was removed from the Formulary. This product has been unavailable and valganciclovir (Valcyte®), which has the same indications, is on the Formulary and offers better oral absorption. Ganciclovir for injection is still available and will remain on the Formulary.

Ø      Griseofulvin (Fulvicin®), an older antifungal agent, is no longer available from the manufacturer and was deleted from the Formulary.

Ø      Norco®, which is a combination of 325mg of acetaminophen and different strengths of hydrocodone may be substituted to same drug combination containing the equivalent amount of hydrocodone.

Ø     In situations of an extreme drug shortage, betamethasone (Celestone®) 12mg IM daily x 2 doses may be switched to dexamethasone (Decadron®) 6mg IM BID x 4 doses for preterm deliveries in antepartum. Betamethasone is available but with maximum order limits.

 

Drug Shortages:

Ø      Bacitracin, which is commonly used in surgery as an antibacterial irrigation, is currently not available. There is now only one manufacturer and they have been unable to maintain sufficient supplies.

Ø      Despite improved supplies of Prevnar® pneumococcal vaccination, a letter from the manufacturer indicates the shortage will continue through June 2004. To help ensure adequate supplies, the CDC recommends suspending the 4^th dose in healthy children.

 

ADE (Adverse Drug Event) Hotline: 655-6805

 

Drug Information Service – 655-2382 (Mon-Fri; 8am – 4pm)