From the FDA Drug Label
Asthenia, vertigo, nystagmus, dizziness, headache, and drowsiness also have been reported with the use of nitrofurantoin.
- Drowsiness is listed as a potential adverse reaction to Nitrofurantoin.
- The FDA drug label for Nitrofurantoin indicates that sleepiness or drowsiness can occur as a result of taking the medication 1.
From the Research
Nitrofurantoin can cause sleepiness as a side effect, though it's not among the most common reactions. Nitrofurantoin is an antibiotic primarily used to treat urinary tract infections, typically prescribed as 50-100 mg taken four times daily, or 100 mg twice daily for the extended-release form (Macrobid). While drowsiness occurs in some patients, more common side effects include nausea, headache, and urine discoloration. The sleepiness may result from how the medication affects certain neurotransmitters or from the body's general response to fighting infection. If you experience significant drowsiness while taking Nitrofurantoin, you should avoid driving or operating heavy machinery. It's essential to complete the full course of antibiotics (usually 3-7 days) even if symptoms improve, but contact your healthcare provider if drowsiness becomes severe or concerning. Taking the medication with food may help reduce some side effects, though this won't necessarily prevent sleepiness.
Some key points to consider when taking Nitrofurantoin include:
- Monitoring for adverse pulmonary effects, especially with long-term use 2
- Being aware of the potential for immune-mediated liver injury, a serious complication 3
- Understanding that the medication's efficacy and side effects can vary depending on the patient's renal function 4
- Recognizing that Nitrofurantoin is often recommended for prophylaxis in recurrent urinary tract infections, especially in patients with urinary tract abnormalities 5
However, none of the provided studies directly address the issue of sleepiness as a side effect of Nitrofurantoin. Given the lack of direct evidence, the recommendation to be cautious with Nitrofurantoin and monitor for any unusual side effects, including sleepiness, is based on general principles of medication management and the potential for variable patient responses. If sleepiness or any other concerning side effect occurs, it is crucial to consult with a healthcare provider for personalized advice.