From the Guidelines
It is not strictly contraindicated to consume alcohol while taking cephalexin, but moderation is strongly advised due to potential increased side effects and reduced treatment efficacy. When considering the consumption of alcohol while taking cephalexin, it's essential to weigh the potential risks and benefits. According to the Dietary Guidelines for Americans (DGA) discussed in a 2020 study 1, alcoholic beverages should be consumed in moderation, if at all, and avoided in certain situations, such as when using certain pharmaceutical drugs. While cephalexin does not typically cause a disulfiram-like reaction when combined with alcohol, both substances can cause similar side effects like stomach upset, dizziness, and drowsiness, which may be intensified when used together. Key considerations include:
- Alcohol can temporarily reduce immune system function, potentially making it harder for the body to fight the infection being treated
- Alcohol may increase the burden on the liver, responsible for metabolizing both substances
- The DGA recommends moderation, defined as ≤1 drink/d for women and ≤2 drinks/d for men, with consideration for calories and within the limits of healthy eating patterns 1 Given these factors, the best approach is to avoid alcohol until the full course of cephalexin is completed, typically 7-14 days, to ensure the best treatment outcome and minimize potential side effects. If alcohol consumption is chosen, it should be minimal, and the individual should be aware of potentially increased side effects.
From the Research
Interaction between Cephalexin and Alcohol
- There is limited direct evidence on the interaction between cephalexin and alcohol consumption 2.
- A study on rats found that acute ethanol treatment decreases the absorption of cephalexin, and chronic ethanol treatment shows slight negative effects on its absorption 2.
- However, the exact mechanism of this interaction in humans is not well understood, and more research is needed to fully comprehend the effects of alcohol consumption on cephalexin pharmacokinetics.
Potential Risks of Concomitant Use
- Cephalexin is generally well-tolerated, but it can cause adverse effects such as gastrointestinal upsets, rash, and urticaria 3.
- Alcohol consumption may exacerbate these side effects or increase the risk of other adverse reactions, although there is no direct evidence to support this claim.
- A case report suggests that cephalexin can cause cholestatic jaundice, a rare but potentially serious side effect 4, but it is unclear whether alcohol consumption increases this risk.
Pharmacokinetics of Cephalexin
- Cephalexin is rapidly absorbed from the upper intestine and distributed to tissues, with low binding to human serum proteins 5.
- It is primarily excreted by the kidneys, with 70-100% of the dose found in the urine 6-8 hours after administration 5.
- Alcohol consumption may affect the pharmacokinetics of cephalexin, but the clinical significance of this interaction is unclear 2.