Nonprescription Analgesics and Their Use in Solid-Organ Transplantation: A Review

Pharmacokinetic Boosting of Calcineurin Inhibitors in Transplantation: Pros, Cons, and Perspectives

ABSTRACT

The concept of pharmacokinetic (PK) boosting of calcineurin inhibitors (CNI) emerged after the FDA approval of cyclosporine-A. Several studies followed, and the proof of concept was well established by the late 1990s. This also continued for the next blockbuster immunosuppressant, tacrolimus. The driver for such research was an endeavor to save costs, as both drugs were expensive due to patent protection. Two CYP inhibitors, ketoconazole and diltiazem, have been extensively studied in this context and continue to be prescribed off-label along with the CNI. It has been observed that using ketoconazole reduces the dose requirement of tacrolimus by about 50% and 30% with diltiazem, which is in conformity with their pharmacological actions. Off-label co-prescription of these drugs with CNI is often encountered in low and middle-income countries. The foremost reason cited is economic. This article collates the evidence from the clinical studies that evaluate the PK-boosting effects of CNI and also reviews the gaps in the current evidence base. The current knowledge prevents the transplant community from making meaningful inferences about the risks and benefits of such strategies. Although the PK-boosting strategy can lead to serious adverse events, emerging evidence suggests that it may be advantageous for individuals with high CNI dose requirements. Hence, PK boosting may be an unmet need in the therapeutics of CNI. Nevertheless, there are several unanswered questions surrounding such use, and therefore, this merits testing in well-designed clinical studies. Moreover, drugs with better safer profiles and a history of successful PK boosting may be considered for evaluation with CNI.

Change of sleep quality from pre- to 3 years post-solid organ transplantation: The Swiss Transplant Cohort Study

BACKGROUND

Poor sleep quality (SQ) is common after solid organ transplantation; however, very little is known about its natural history. We assessed the changes in SQ from pre- to 3 years post-transplant in adult heart, kidney, liver and lung recipients included in the prospective nation-wide Swiss Transplant Cohort Study. We explored associations with selected variables in patients suffering persistent poor SQ compared to those with good or variable SQ.

METHODS

Adult single organ transplant recipients enrolled in the Swiss Transplant Cohort Study with pre-transplant and at least 3 post-transplant SQ assessment data were included. SQ was self-reported pre-transplant (at listing), then at 6, 12, 24 and 36 months post-transplant. A single SQ item was used to identify poor (0-5) and good sleepers (6-10). Between organ groups, SQ was compared via logistic regression analysis with generalized estimating equations. Within the group reporting persistently poor SQ, we used logistic regression or Kaplan-Meier analysis as appropriate to check for differences in global quality of life and survival.

RESULTS

In a sample of 1173 transplant patients (age: 52.1±13.2 years; 65% males; 66% kidney, 17% liver, 10% lung, 7% heart) transplanted between 2008 and 2012, pre- transplant poor SQ was highest in liver (50%) and heart (49%) recipients. Overall, poor SQ decreased significantly from pre-transplant (38%) to 24 months post-transplant (26%) and remained stable at 3 years (29%). Patients reporting persistently poor SQ had significantly more depressive symptomatology and lower global quality of life.

CONCLUSION

Because self-reported poor SQ is related to poorer global quality of life, these results emphasize the need for further studies to find suitable treatment options for poor SQ in transplant recipients.

Recommendations for the proper use of nonprescription cough suppressants and expectorants in solid-organ transplant recipients

OBJECTIVE

To describe the pharmacology and safety of oral over-the-counter cough suppressants and expectorants and to present recommendations for the use of these agents in solid-organ transplant recipients based on the potential for adverse drug reactions or drug-disease interactions.

DATA SOURCES AND EXTRACTION

Data from journal articles and other sources describing the pharmacology and safety of over-the-counter cough suppressants and expectorants, drug-drug interactions with immunosuppressive agents, and drug-disease state interactions are reviewed.

DATA SYNTHESIS

Potential and documented drug-drug interactions between immunosuppressive agents and over-the-counter cough medications guaifenesin, dextromethorphan, diphenhydramine, and codeine were evaluated on the basis of pharmacokinetic and pharmacodynamic principles. Interactions between these cough medications and the physiological changes in the body following transplantation also were examined.

CONCLUSION

Diphenhydramine requires additional monitoring when used to treat cough in transplant recipients owing to its anticholinergic properties and the potential for interactions with cyclosporine. Dextromethorphan can be used in most transplant recipients, although greater caution should be exercised if the patient has undergone liver transplant or has liver impairment. Guaifenesin can be used in transplant recipients but should be used with caution in patients receiving kidney or lung transplants and in patients with renal impairment. Codeine combined with guaifenesin is another option for cough and can be used in most transplant patients although those with reduced renal function should be monitored carefully for adverse events.

Recommendations for the Proper Use of Nonprescription Cough Suppressants and Expectorants in Solid-Organ Transplant Recipients

Objective

To describe the pharmacology and safety of oral over-the-counter cough suppressants and expectorants and to present recommendations for the use of these agents in solid-organ transplant recipients based on the potential for adverse drug reactions or drug-disease interactions.

Data Sources and Extraction

Data from journal articles and other sources describing the pharmacology and safety of over-the-counter cough suppressants and expectorants, drug-drug interactions with immunosuppressive agents, and drug-disease state interactions are reviewed.

Data Synthesis

Potential and documented drug-drug interactions between immunosuppressive agents and over-the-counter cough medications guaifenesin, dextromethorphan, diphenhydramine, and codeine were evaluated on the basis of pharmacokinetic and pharmacodynamic principles. Interactions between these cough medications and the physiological changes in the body following transplantation also were examined.

Conclusion

Diphenhydramine requires additional monitoring when used to treat cough in transplant recipients owing to its anticholinergic properties and the potential for interactions with cyclosporine. Dextromethorphan can be used in most transplant recipients, although greater caution should be exercised if the patient has undergone liver transplant or has liver impairment. Guaifenesin can be used in transplant recipients but should be used with caution in patients receiving kidney or lung transplants and in patients with renal impairment. Codeine combined with guaifenesin is another option for cough and can be used in most transplant patients although those with reduced renal function should be monitored carefully for adverse events.