iCliniq Logo
HomeAnswersGeneral Medicineheadache

What causes headaches and blood in stool once a month?

This Premium Q&A, reviewed and published, features a real conversation between an iCliniq user and a physician.

Patient's Query

Hello doctor,

I have been experiencing headaches on one side and blurred vision. I also have blood in my stool that comes and goes about once a month.

I take Seroquel and Melatonin for sleeping.

Please help.

Thank you.

Hi,

Welcome to icliniq.com.

I read your query and can understand your concern.

It is important to address each of your concerns individually, especially since you are experiencing multiple symptoms.

The main key symptoms are headache and blurred vision (on one side).

The possible causes related to your condition are

  1. Prolonged periods of computer gaming or screen use can lead to digital eye strain, which may result in headaches, eye fatigue, and blurred vision. This is common in individuals who spend extended time in front of screens without taking breaks.
  2. Migraines or cluster headaches can cause one-sided headaches accompanied by visual disturbances, such as blurred vision or auras (flashing lights or visual patterns). If this is a recurring issue, it may indicate a migraine disorder.
  3. If you are taking Seroquel (Quetiapine) or melatonin, be aware that both medications can cause drowsiness and, in some cases, blurred vision or dizziness. These effects are more likely when starting a new medication or increasing the dosage.

The possible causes of blood in stool (intermittent, occurring about once a month or every two months) are

  1. Hemorrhoids, a very common cause of bright red blood in the stool, especially if it occurs occasionally. Hemorrhoids may result from straining during bowel movements, prolonged sitting, or constipation.
  2. Anal fissures or gastrointestinal irritation, small tears in the anal lining, or irritation from hard stools can also lead to intermittent bleeding.
  3. Inflammatory bowel disease (IBD), a condition such as Crohn’s disease or ulcerative colitis, may cause recurring gastrointestinal bleeding, especially if other symptoms such as abdominal pain or changes in bowel habits are present.
  4. Polyps in the colon or rectum can sometimes cause intermittent bleeding. While many polyps are benign, it is important to have them evaluated.

I will recommend the next steps for headache and vision issues:

  1. Practice screen hygiene by following the 20-20-20 rule, like every 20 minutes, looking at something 20 feet away for at least 20 seconds. Adjust the brightness and contrast of your screen and consider using blue light-blocking glasses.
  2. Schedule an appointment with an optometrist (vision care specialist) or ophthalmologist (eye specialist) to rule out any underlying vision problems or eye strain issues.
  3. If the headaches are recurrent and one-sided, especially with visual symptoms like auras or blurred vision, consult a primary care physician or neurologist to assess for migraine headaches.

I will recommend the next steps for blood in stool:

Given that this symptom has persisted intermittently for more than a year, a specialist should evaluate your gastrointestinal tract. Recommended diagnostic tests may include:

  1. Colonoscopy or sigmoidoscopy to identify any polyps, inflammation, or signs of conditions like IBD (inflammatory bowel disease) or diverticulosis (a condition where small, bulging pouches form in the lining of the colon).
  2. Stool tests to detect hidden (occult) blood, infections, or other abnormalities.
  3. Rectal examination to check for hemorrhoids or anal fissures.

Review your medications:

  1. Seroquel (Quetiapine) is an antipsychotic medication that may cause blurred vision, dizziness, or drowsiness, particularly when starting treatment or changing the dosage. If these side effects are worsening, it is important to speak with the prescribing healthcare provider about possible adjustments.
  2. Melatonin, while generally well-tolerated, can occasionally cause side effects such as headaches or drowsiness. Visual disturbances are less common but still possible.
  3. If your symptoms seem linked to your medications, consult your healthcare provider about whether a dosage change or alternative treatment may be appropriate.

You should see an eye doctor to evaluate your vision and address potential issues, such as eye strain or undiagnosed visual problems, and consult a gastroenterologist to investigate the cause of the blood in your stool through appropriate diagnostic tests.

Talk to your prescribing doctor about your current medications, especially if symptoms like headaches and blurred vision have worsened. Get a full medical evaluation to rule out any serious conditions, including inflammatory bowel disease, colon polyps, or other gastrointestinal disorders.

I hope this helps.

Kindly revert so I can assist you further.

Thank you.

Medically reviewed byiCliniq medical review team

Published At June 3, 2025
Reviewed AtApril 15, 2026

Same symptoms don't mean you have the same problem. Consult a doctor now!

Listen to related tracks in our music library

Ask your health query to a doctor online

*guaranteed answer within 4 hours

Disclaimer: No content published on this website is intended to be a substitute for professional medical diagnosis, advice or treatment by a trained physician. Seek advice from your physician or other qualified healthcare providers with questions you may have regarding your symptoms and medical condition for a complete medical diagnosis. Do not delay or disregard seeking professional medical advice because of something you have read on this website. Read our Editorial Process to know how we create content for health articles and queries.