In patients with myasthenia gravis, certain antibiotics are contraindicated due to their potential to exacerbate muscle weakness. These include:

1. Aminoglycosides (e.g., gentamicin, tobramycin)

2. Fluoroquinolones (e.g., ciprofloxacin, levofloxacin)

3. Macrolides (e.g., erythromycin, azithromycin)

4. Tetracyclines (e.g., doxycycline)

Similarly, for patients with cerebral palsy, who also experience muscle weakness, these antibiotics should be used with caution or avoided. Additional medications that may worsen muscle weakness in CP patients include:

1. Anticonvulsants: Such as phenytoin, which can further compromise muscle function.

2. Muscle relaxants: Such as baclofen, which can induce additional muscle weakness.

3. Sedatives: Including benzodiazepines (e.g., diazepam), due to their potential to increase muscle weakness and sedation.

It is important to evaluate the risks and benefits when prescribing these medications to patients with myasthenia gravis or cerebral palsy.