Is Buscopan (hyoscine butylbromide) safe for a pregnant woman in her first trimester with severe pain due to a urinary tract infection (UTI)?

Buscopan (Hyoscine Butylbromide) for First Trimester UTI Pain

Do not use Buscopan for severe UTI pain in the first trimester—instead, treat the underlying infection with appropriate antibiotics and use acetaminophen for pain relief, as hyoscine butylbromide is Pregnancy Category C with no adequate human safety data and should only be given to pregnant women if clearly needed. 1

Why Buscopan Is Not the Right Choice

Lack of Safety Data in Pregnancy

• The FDA drug label explicitly states that animal reproduction studies have not been conducted with hyoscine butylbromide, and it is not known whether it can cause fetal harm when administered to a pregnant woman 1
• Hyoscine butylbromide is classified as Pregnancy Category C, meaning it should be given to a pregnant woman "only if clearly needed" 1
• There are no adequate and well-controlled studies in pregnant women to establish safety during the critical first trimester of organogenesis 1

The Real Problem Requires Antibiotic Treatment

• The primary issue is the UTI itself, not just the pain—untreated UTIs in pregnancy carry severe risks that far outweigh concerns about symptomatic relief. 2, 3
• Pregnant women with untreated asymptomatic bacteriuria have a 20-30-fold increased risk of developing pyelonephritis compared to women without bacteriuria 2
• Without antibiotic treatment, pyelonephritis develops in 20-35% of pregnant women with bacteriuria, compared to only 1-4% when treated 2, 4
• Untreated UTIs are associated with premature delivery, low birth weight infants, preterm labor, and other adverse maternal and fetal outcomes 2, 3, 4

The Correct Management Approach

Immediate Antibiotic Therapy

• For symptomatic UTI in the first trimester, initiate amoxicillin 500 mg three times daily for 3-7 days as first-line therapy. 5
• Alternative first-line options include nitrofurantoin, fosfomycin, or third-generation cephalosporins if the organism is susceptible 2, 4
• Obtain urine culture before initiating empirical antimicrobial treatment to guide subsequent therapy 6
• Repeat urine cultures seven days following therapy to assess cure or failure 5

Pain Management That Is Safe

• Use acetaminophen (paracetamol) for pain relief during first trimester—it is the safest analgesic option in pregnancy.
• Adequate hydration and frequent voiding can help reduce dysuria and suprapubic discomfort 7

When to Escalate Care

• If the patient develops high fever, flank pain, vomiting, or signs of systemic illness, this indicates pyelonephritis requiring hospitalization 6
• Pregnant women with upper UTI (pyelonephritis) should be managed in a hospital setting with intravenous antibiotics 6
• Second-generation cephalosporins are the suggested first option for empirical management of upper UTI in pregnancy 6

Critical Pitfalls to Avoid

• Do not delay antibiotic therapy to focus on symptomatic relief alone—this significantly increases the risk of progression to pyelonephritis with its associated maternal and fetal complications. 2
• Do not use fluoroquinolones during pregnancy due to potential fetal risks 6, 4
• Do not rely on antispasmodics like Buscopan when the underlying infection requires definitive antimicrobial treatment 2
• Do not assume that pain relief addresses the infection—as many as one third of pregnant women with UTIs will experience recurrence and require close follow-up 3

Why This Matters in the First Trimester

• The first trimester is the period of organogenesis when the fetus is most vulnerable to teratogenic effects 1
• Screening for asymptomatic bacteriuria at 12-16 weeks gestation is critical because untreated bacteriuria carries a 20-35% risk of progression to pyelonephritis 2
• Low birth weight and preterm birth are significantly associated with untreated UTIs during pregnancy, making early and appropriate treatment essential 2, 4