Many people rely on cold and flu tablets to relieve nasal congestion during winter illnesses. However, research shows that the most common oral decongestant, phenylephrine, does not work well when swallowed, raising questions about the efficacy of these widely sold medicines.
- Phenylephrine works well as a nasal spray but not as an oral tablet.
- Pseudoephedrine, a stronger alternative, became harder to buy due to misuse concerns.
- Regulators worldwide are reviewing the effectiveness of oral phenylephrine.
What happened
Many cold and flu tablets contain phenylephrine, an oral decongestant intended to relieve nasal congestion by narrowing blood vessels in the nose. However, growing evidence reveals that phenylephrine in pill form is largely ineffective because only a tiny fraction enters the bloodstream to reach nasal tissues.
Previously, pseudoephedrine was the primary decongestant used in tablets and nasal sprays. Due to its use in illicit drug production, regulatory controls tightened, restricting its availability and leading manufacturers to replace it with phenylephrine. Despite early optimism, recent studies and regulatory reviews question phenylephrine’s real benefit when taken orally, though it remains common in over-the-counter remedies.
Why it feels good
Cold and flu tablets often include multiple ingredients such as pain relievers and antihistamines, which might reduce overall symptoms like aches, fever, and runny nose, giving a sense of relief even if nasal congestion remains stubborn. The perception of improvement can also be influenced by the placebo effect.
Since phenylephrine nasal sprays deliver the drug directly to the nasal passages, they generally provide faster and more effective congestion relief. However, tablets remain popular because they are easier to use, widely accessible, and taken alongside other symptom-relief components which can help with discomfort.
What to enjoy or watch next
Medical regulators such as the US Food and Drug Administration are actively considering removing oral phenylephrine from cold and flu tablets due to lack of effectiveness, while Australian authorities continue monitoring the situation. Consumers may want to look for alternatives like nasal sprays or consult pharmacists for effective options.
In the meantime, focusing on supportive care—rest, hydration, and managing symptoms with proven remedies—remains key during cold and flu season. Staying informed about evolving regulatory and scientific guidance can help people make better choices about cold and flu treatments.