LETTERS
Pharmacists have a key role in raising awareness around risks of intranasal desmopressin The prevalence of bleeding disorders is approximately 1 in 1000, and patients with this disorder will occasionally present a prescription for intranasal desmopressin to a community pharmacy.1 The availability of two different desmopressin nasal spray concentrations is a potential cause of confusion and error when used for bleeding disorders such as mild hemophilia A (factor VIII deficiency) and von Willebrand disease (VWD). It has come to our attention that some bleeding disorder patients prescribed the high concentration intranasal desmopressin for home use are dispensed the lower strength desmopressin products, resulting in subtherapeutic doses and an unnecessary risk of bleeding complications. At our clinic alone, we have identified four such cases in the past year, while others may continue to go unnoticed. To our knowledge, this is the first report of medication errors involving desmopressin used for bleeding disorders. In light of the multiple indications and strengths of desmopressin products, community pharmacists play a key role in ensuring that these patients receive the prescribed therapy. Herein, we aim to raise awareness regarding the potential for error and to offer guidance in assessing and dispensing intranasal desmopressin prescriptions. Standard intranasal desmopressin doses in bleeding disorders are typically 150–300 mcg, which can only be delivered using desmopressin (Stimate—CSL Behring) 1.5 mg/ mL, as opposed to lower strength products including desmopressin (Minirin—Ferring; DDAVP—Sanofi-Aventis) 0.1 mg/mL and generics. A dose of 150–300 mcg is necessary to treat and prevent bleeding episodes, and to manage severe menorrhagia. This is accomplished primarily by the release of von Wil460 JAPhA | 5 4:5 | S E P /OCT 2 0 1 4
lebrand factor (VWF) and coagulation factor VIII from vascular endothelium following the interaction of desmopressin with vasopressin type 2 receptors.2 VWF is a coagulation protein that interacts with platelets, allowing platelets to adhere to the injured vascular endothelium and eventually form the primary platelet plug.3 VWF also circulates bound to clotting factor VIII and this serves to prolong intravascular factor VIII survival.3 Desmopressin is also indicated for central diabetes insipidus (CDI) and primary nocturnal enuresis (PNE), but at substantially lower doses unsuitable for delivery by Stimate). CDI is caused by rapid water loss through urine due to a lack of vasopressin. As a synthetic analogue of vasopressin, desmopressin can prevent dehydration in CDI by altering renal tubule permeability to increase water resorption.4 This mechanism of concentrating urine and limiting urine production also underlies the use of desmopressin in the treatment of PNE. In 2007, an alert regarding desmopressin was issued by the U.S. Food and Drug Administration (FDA) due to an increased risk of hyponatremia and seizures secondary to water retention.5 As a result, intranasal desmopressin became contraindicated for PNE, leaving the safer oral tablet as the alternative.5 The alert was accompanied by updated desmopressin prescribing information regarding hyponatremia risk and safe use in susceptible patients.5 Because these safety alerts were issued in the United States and Canada, we expect practice patterns of desmopressin use to be similar in both countries. Therefore, if prescribed for bleeding disorders, only the higher concentration desmopressin (Stimate) is appropriate. At the time of dispensing, errors may arise in product selection as intranasal desmopressin (Stimate) is not a commonly dispensed product and may be unlisted in wholesaler catalogues. This can lead to ja p h a.org
the erroneous conclusion that it is unavailable and substitution with a low and ineffective concentration. Pharmacists are in an optimal position to prevent these situations since they can clarify the indication for desmopressin with the prescribing physician and verify product status using the online Drugs@FDA database managed by FDA. A quick search for desmopressin reveals the active status of Stimate and generics. In Canada, the equivalent product goes by a different brand name, Octostim—Ferring, and no generics are currently available. An awareness of the two available strengths of desmopressin and their appropriate indications is essential for correct dosing. Community pharmacists are the most suitable health care professionals to help improve bleeding disorder patient outcomes with regards to intranasal desmopressin use. Should a medication error occur, we encourage reporting the incident to FDA, Health Canada, or the Institute for Safe Medication Practices, as appropriate. A few extra moments of investigation could make all the difference. Jaime Kwok, BScPharm University of British Columbia Vancouver, BC Deb Gue, RN, MSN Clinical Nurse Specialist Hemophilia Program of British Columbia Adult Division St. Paul’s Hospital Vancouver, BC Jeff Curtis, BScPharm Pharmacy Manager/Owner Macdonald’s Prescriptions Ltd. Vancouver, BC Shannon Jackson, MD Medical Director Hemophilia Program of British Columbia Adult Division St. Paul’s Hospital Vancouver, BC [email protected] doi: 10.1331/JAPhA.2014.14538
Journal of the American Pharmacists Association
Pharmacists have a key role in raising awareness around risks of intranasal desmopressin The prevalence of bleeding disorders is approximately 1 in 1000, and patients with this disorder will occasionally present a prescription for intranasal desmopressin to a community pharmacy.1 The availability of two different desmopressin nasal spray concentrations is a potential cause of confusion and error when used for bleeding disorders such as mild hemophilia A (factor VIII deficiency) and von Willebrand disease (VWD). It has come to our attention that some bleeding disorder patients prescribed the high concentration intranasal desmopressin for home use are dispensed the lower strength desmopressin products, resulting in subtherapeutic doses and an unnecessary risk of bleeding complications. At our clinic alone, we have identified four such cases in the past year, while others may continue to go unnoticed. To our knowledge, this is the first report of medication errors involving desmopressin used for bleeding disorders. In light of the multiple indications and strengths of desmopressin products, community pharmacists play a key role in ensuring that these patients receive the prescribed therapy. Herein, we aim to raise awareness regarding the potential for error and to offer guidance in assessing and dispensing intranasal desmopressin prescriptions. Standard intranasal desmopressin doses in bleeding disorders are typically 150–300 mcg, which can only be delivered using desmopressin (Stimate—CSL Behring) 1.5 mg/ mL, as opposed to lower strength products including desmopressin (Minirin—Ferring; DDAVP—Sanofi-Aventis) 0.1 mg/mL and generics. A dose of 150–300 mcg is necessary to treat and prevent bleeding episodes, and to manage severe menorrhagia. This is accomplished primarily by the release of von Wil460 JAPhA | 5 4:5 | S E P /OCT 2 0 1 4
lebrand factor (VWF) and coagulation factor VIII from vascular endothelium following the interaction of desmopressin with vasopressin type 2 receptors.2 VWF is a coagulation protein that interacts with platelets, allowing platelets to adhere to the injured vascular endothelium and eventually form the primary platelet plug.3 VWF also circulates bound to clotting factor VIII and this serves to prolong intravascular factor VIII survival.3 Desmopressin is also indicated for central diabetes insipidus (CDI) and primary nocturnal enuresis (PNE), but at substantially lower doses unsuitable for delivery by Stimate). CDI is caused by rapid water loss through urine due to a lack of vasopressin. As a synthetic analogue of vasopressin, desmopressin can prevent dehydration in CDI by altering renal tubule permeability to increase water resorption.4 This mechanism of concentrating urine and limiting urine production also underlies the use of desmopressin in the treatment of PNE. In 2007, an alert regarding desmopressin was issued by the U.S. Food and Drug Administration (FDA) due to an increased risk of hyponatremia and seizures secondary to water retention.5 As a result, intranasal desmopressin became contraindicated for PNE, leaving the safer oral tablet as the alternative.5 The alert was accompanied by updated desmopressin prescribing information regarding hyponatremia risk and safe use in susceptible patients.5 Because these safety alerts were issued in the United States and Canada, we expect practice patterns of desmopressin use to be similar in both countries. Therefore, if prescribed for bleeding disorders, only the higher concentration desmopressin (Stimate) is appropriate. At the time of dispensing, errors may arise in product selection as intranasal desmopressin (Stimate) is not a commonly dispensed product and may be unlisted in wholesaler catalogues. This can lead to ja p h a.org
the erroneous conclusion that it is unavailable and substitution with a low and ineffective concentration. Pharmacists are in an optimal position to prevent these situations since they can clarify the indication for desmopressin with the prescribing physician and verify product status using the online Drugs@FDA database managed by FDA. A quick search for desmopressin reveals the active status of Stimate and generics. In Canada, the equivalent product goes by a different brand name, Octostim—Ferring, and no generics are currently available. An awareness of the two available strengths of desmopressin and their appropriate indications is essential for correct dosing. Community pharmacists are the most suitable health care professionals to help improve bleeding disorder patient outcomes with regards to intranasal desmopressin use. Should a medication error occur, we encourage reporting the incident to FDA, Health Canada, or the Institute for Safe Medication Practices, as appropriate. A few extra moments of investigation could make all the difference. Jaime Kwok, BScPharm University of British Columbia Vancouver, BC Deb Gue, RN, MSN Clinical Nurse Specialist Hemophilia Program of British Columbia Adult Division St. Paul’s Hospital Vancouver, BC Jeff Curtis, BScPharm Pharmacy Manager/Owner Macdonald’s Prescriptions Ltd. Vancouver, BC Shannon Jackson, MD Medical Director Hemophilia Program of British Columbia Adult Division St. Paul’s Hospital Vancouver, BC [email protected] doi: 10.1331/JAPhA.2014.14538
Journal of the American Pharmacists Association
