Does doxycycline (antibiotic) cause hyperhidrosis (excessive sweating)?

Doxycycline and Hyperhidrosis

Doxycycline does not cause excessive sweating (hyperhidrosis) as a common or documented side effect. Based on the available guidelines, hyperhidrosis is not listed among the known adverse effects of doxycycline 1.

Known Side Effects of Doxycycline

The British Thoracic Society guidelines clearly document the adverse effects of doxycycline, which include:

Common side effects:

• Photosensitivity and skin rash
• Gastrointestinal disturbances (nausea, vomiting, diarrhea, dysphagia) 1
• Esophagitis, particularly with inadequate fluid intake 1, 2

Serious but less common side effects:

• Dermatological reactions (exfoliative dermatitis, erythema multiforme, Stevens-Johnson syndrome)
• Hepatotoxicity (hepatitis, jaundice)
• Hematological effects (hemolytic anemia, thrombocytopenia)
• Neurological effects (benign intracranial hypertension)
• Immunological reactions (anaphylaxis) 1

Gastrointestinal Side Effects - Most Common

Gastrointestinal side effects are the most frequently reported adverse effects of doxycycline:

• Occur in approximately 15.7% of patients (vs 5.9% with placebo) 1
• Higher incidence with 200mg daily dosing compared to 100mg daily 2
• More common in patients ≥50 years old 2

To minimize these effects:

• Take with food and adequate fluids
• Remain upright after taking the medication
• Consider delayed-release formulations which have shown lower rates of nausea (13% vs 21%) and vomiting (8% vs 12%) compared to immediate-release formulations 3

Photosensitivity - Important Consideration

Doxycycline can sensitize the skin to sunlight, resulting in:

• Greater likelihood of sunburn with exposure
• Photosensitivity reactions 1

Special Considerations

1. Contraindications:

   • Children under 8 years (risk of permanent teeth discoloration)
   • Pregnancy and breastfeeding
   • Hypersensitivity to tetracyclines 1

2. Drug interactions:

   • Reduced absorption with aluminum-containing preparations (take doxycycline 2-3 hours before or after)
   • Reduced serum levels in alcoholic patients 1
   • May decrease effectiveness of oral contraceptives 1

Hyperhidrosis and Antibiotics

While doxycycline is not associated with hyperhidrosis, it's worth noting that:

1. Some research suggests that certain skin conditions involving hyperhidrosis may actually improve with antibiotic treatment (though with erythromycin, not doxycycline) 4

2. For patients with hyperhidrosis as a primary condition, specific pharmacological treatments are recommended rather than antibiotics 5

Monitoring Recommendations

For patients on doxycycline:

• Monitor for gastrointestinal symptoms
• Advise about photosensitivity and sun protection
• Perform routine toxicity monitoring tests (FBC, U&Es, LFTs) intermittently throughout treatment 1

In conclusion, while doxycycline has several well-documented side effects, hyperhidrosis (excessive sweating) is not among them based on current clinical guidelines and research evidence.