Effect of Acetaminophen use during pregnancy on adverse pregnancy outcomes: a systematic review and meta-analysis.

INTRODUCTION: A high number of women are exposed to acetaminophen during pregnancy worldwide. This drug safety during pregnancy regarding preterm birth, birth weight, and fetal development has not been well described. This study investigated the effect of acetaminophen use during pregnancy on selected adverse pregnancy outcomes. AREAS COVERED: Databases were searched to identify studies reporting the effects of acetaminophen use during pregnancy on preterm birth, low birth weight, and small for gestational age. The studies' quality was assessed by the Newcastle-Ottawa Scale and the Methodological Index for Non-Randomized Studies. Risk ratios with 95% confidence intervals were estimated using a fixed or random-effects model. Six studies were included for final review, four cohort and two case-control studies. We found no increased risk of preterm birth (RR 0.97; 95% CI 0.59-1.58), and decreased risks of low birth weight (RR 0.65; 95% CI 0.59-0.72) and small for gestational age (RR 0.69; 95% CI 0.50-0.97). Acetaminophen exposure during the third trimester revealed non-significantly in the outcomes. EXPERT OPINION: Exposure to acetaminophen during pregnancy appears to not increase the risk of the outcomes analyzed. However, there is a lack of information regarding the exposure dose and frequency of acetaminophen use.

Factors associated with older patients' misunderstandings of medication dosage regimen instructions after consultation in primary care in Brazil.

RATIONALE, AIMS, AND OBJECTIVES: Misunderstanding medication dosage regimen instructions can lead to unintentional misuse of a prescribed medicine, non-adherence to providers' instructions, and other treatment-related issues. We aimed to evaluate the frequency of and factors associated with older patients' misunderstanding of medication dosage regimen instructions after consultation with a general practitioner. METHOD: This cross-sectional study was conducted in 22 primary-care facilities in Brazil. Data were collected from September 2016 to December 2017 using a multidimensional questionnaire. Patients who were 60 years old or older who visited primary care units were included in the study (n = 416). RESULTS: Of the older patients interviewed, 38.2% had a misunderstanding of medication dosage regimen instructions; being female was a protective factor against the misunderstanding of medication dosage regimen instructions (prevalence ratio [PR] = 0.63; 95% confidence interval [CI] = 0.45-0.89). In relation to other factors with an important association, misunderstanding medication dosage regimen instructions was 71% higher among illiterate participants (PR = 1.71; 95% CI = 1.25-2.35), 39% higher among people who considered their memory to be poor (PR = 1.39; 95% CI = 1.01-1.91), 49% higher in those who did not have a job at the time of the interview (PR = 1.49; 95% CI = 1.01-2.19), and 50% higher in patients who had been prescribed five or more medications (PR = 1.50; 95% CI = 1.02-2.20). CONCLUSIONS: The results showed that older people's misunderstandings of medication dosage regimen instructions after consultation with a general practitioner was greater than expected due to a range of factors, especially polypharmacy, poor literacy, poor memory, and having a job at the time of the interview. Health services and professionals should implement strategies to increase the quality of the guidance given to elderly individuals and to ensure their adherence to the regimen instructions of their medications.