Some of the most popular side effects of Clomid include ovarian enlargement, headache, bloating, flushing, nausea, vomiting, breast tenderness, uterine bleeding, and spotting. Some people also feel blurred vision, double vision, sensitivity to light, lights, floaters, and so on.

A general allergic reaction to any drug has these symptoms: difficulty breathing, swelling or closing of throat, hives, swelling of face or tongue, rash, open sores, bruising or worsening respiratory symptoms. These symptoms indicate that you may be allergic to Clomid. Get medical attention immediately.
A dangerous and sometimes fatal side effect is ovarian hyper-stimulation syndrome.
Get immediate medical attention if you experience, swelling of legs or hands, abdominal pain, abdominal swelling, weight gain, nausea, vomiting or shortness of breath.
Other side effects from this medication should be discussed with your doctor should they occur, are: diarrhea, headache, atypical bleeding from the vagina, blurred vision or impaired vision, and breast pain or breast sensitivity.

Also it's stroke, acne, itchy skin, chest pain, numbness or tingling, seizure, anxiety, cataracts, eye pain, back pain, fluid in the eyes, temporary blindness, muscle pain, liver inflammation, several different types of neoplasms, endometriosis, ringing in the ears, migraines, fever. Also there are rare, occurring in fewer than one percent of patients, and can include increased appetite, constipation or diarrhea, dizziness, depression or fatigue, hair loss, rash, increase in volume or frequency or urine, vaginal dryness, weight gain or loss, ovarian cysts.