Hello and welcome to HCM.
Thank you for your query.
I can understand your concern. Chlamydia is usually treated with either of the two antibiotics:
Azithromycin (single dose)
Doxycycline (longer course)
As doxycycline is no advised in pregnant women, we are left with only azithromycin, although there are other treatment options available, I feel azithromycin is the best option.
A 1gm (1000 mg) single dose of azithromycin is usually prescribed to treat chlamydia. But as you seem to be suffering from a reaction from the same, the only other option would be to break down the dosage of 1000 mg through the day; and later test for chlamydia. Hoping the infection has been treated with successfully, the course might not be repeated, but if not, then it might have to be repeated again. Unfortunately as you are suffering from such a reaction, we will have to take it easy and slowly. If you do not respond to even the second course, then your doctor will have to choose other antibiotics weighing the risks and benefits of the drugs. (eg. eryhtromycin, etc.)
I hope I have succeeded in providing the information you were looking for. Please feel free to write back to me for any further clarifications at: http://doctor.healthcaremagic.com/doctors/dr-shoaib-khan/64581 . I would gladly help you.
Best wishes.