Does Bactrim (Trimethoprim/Sulfamethoxazole) cause a dry cough?

From the Guidelines

Bactrim (sulfamethoxazole-trimethoprim) can cause a dry cough in some patients, although it is not among the most common side effects, as noted in studies such as 1 and 1.

Common Side Effects

The mechanism of this side effect involves either direct irritation of the respiratory tract or an immune-mediated reaction to the medication.

• Other common side effects of Bactrim include skin rash, gastrointestinal disturbances, and photosensitivity.
• Staying well-hydrated while taking Bactrim may help minimize some side effects, but it won't necessarily prevent a medication-induced cough.

Clinical Considerations

If you develop a persistent dry cough while taking Bactrim, you should contact your healthcare provider, as this could potentially indicate a hypersensitivity reaction or lung inflammation.

• Don't stop taking the medication without medical advice, but your doctor may need to evaluate whether the cough is medication-related or has another cause.
• The evidence from studies like 1 and 1 highlights the importance of monitoring for adverse effects when prescribing Bactrim, especially in patients with a history of respiratory issues or those who are prone to allergic reactions.

Management and Prevention

In the context of managing and preventing dry cough associated with Bactrim use, it's crucial to follow the recommended dosage and to complete the full course of treatment as prescribed by your healthcare provider.

• Patients receiving TMP-SMZ might experience gastrointestinal adverse effects, hypersensitivity skin reactions, and rarely, Stevens-Johnson syndrome, toxic epidermal necrolysis, blood dyscrasias, and hepatic necrosis, as mentioned in 1.
• Given the potential for serious side effects, the decision to use Bactrim should be made with caution, especially in vulnerable populations such as the elderly, pregnant women, and those with impaired renal or hepatic function, as discussed in 1 and 1.

From the FDA Drug Label

Cough, shortness of breath and pulmonary infiltrates potentially representing hypersensitivity reactions of the respiratory tract have been reported in association with sulfamethoxazole and trimethoprim treatment Cough, shortness of breath, and pulmonary infiltrates are hypersensitivity reactions of the respiratory tract that have been reported in association with sulfonamide treatment.

Bactrim (Trimethoprim/Sulfamethoxazole) may cause a dry cough as part of a hypersensitivity reaction of the respiratory tract.

• The FDA drug label reports cough as a potential adverse reaction associated with sulfamethoxazole and trimethoprim treatment 2 3.
• However, it is not explicitly stated that the cough is dry.
• Given the information available, it is possible that Bactrim may cause a dry cough, but this cannot be confirmed with certainty.

From the Research

Bactrim (Trimethoprim/Sulfamethoxazole) and Dry Cough

• There is limited direct evidence linking Bactrim (Trimethoprim/Sulfamethoxazole) to a dry cough 4, 5.
• However, a study published in 2001 reported a case of drug-induced pneumonitis caused by sulfamethoxazole-trimethoprim, which presented with symptoms including a productive cough, but it is not specified as a dry cough 6.
• Another study published in 2020 found that patients with idiopathic pulmonary fibrosis who received co-trimoxazole (trimethoprim-sulfamethoxazole) had no significant difference in cough severity compared to those who received a placebo 7.
• A 2021 systematic review and meta-analysis found that low-dose trimethoprim-sulfamethoxazole had a decreased rate of adverse reactions, including respiratory-related events, compared to conventional dosing, but it does not specifically mention dry cough 8.

Adverse Reactions

• The 2020 study found that patients in the co-trimoxazole group had adverse events such as nausea, diarrhea, vomiting, and rash, but dry cough was not specifically mentioned 7.
• The 2021 systematic review and meta-analysis found that low-dose trimethoprim-sulfamethoxazole had a decreased rate of adverse reactions, including respiratory-related events, but it does not provide detailed information on specific adverse reactions such as dry cough 8.