You are having a reaction to a medicine you have taken. This may not be the same as an allergic reaction. It's an unwanted side effect of a medicine. This can cause many symptoms, such as:
- Dizziness or headache.
- Rash.
- Flushing or a hot feeling.
- Nausea, vomiting, or stomach pain.
- Diarrhea or constipation.
- Trouble breathing.
- High or low blood pressure.
- Dark urine or blood in urine.
A reaction can be an upset stomach from something such as aspirin or ibuprofen. It can also be feeling faint after taking a blood pressure medicine, feeling anxious, and many other things. Symptoms can range from very mild to very severe.
In most cases, the reaction goes away in 1 to 12 hours. But it will likely happen again if you take this same medicine. Your doctor will advise you if you need to change how much, when, or how often you take this medicine. They may also advise you to stop using this medicine. Or your doctor may have you switch to another one. Ask your doctor if your symptoms were an allergic reaction or a side effect of the medicine.
Home care
- Another medicine may be advised to reduce your symptoms. Follow your doctor's advice about how long to take this additional medicine.
- When the medicine's effect has worn off, there should be no more problems if you don't take the same medicine again.
- Ask your doctor if you should also stay away from similar medicines. Write down the medicine information and your reactions to it, to help you remember what happened.
- Be sure the medicine reaction is put into your health record.
Follow-up care
Follow up with your doctor, or as advised if your symptoms are not better in 24 hours.
When to get medical advice
Contact your doctor or seek medical care right away if:
- You have new symptoms that worry you.
- Your current symptoms get worse.
- Your symptoms are not eased by the treatment advised.
- You have a fever of 100.4°F (38°C) or higher, or as advised by your doctor.
- You have chills.
Call 911
Call
- Trouble breathing or swallowing, or if you are wheezing.
- A hoarse voice or trouble speaking.
- Confusion.
- Extreme drowsiness or trouble waking up.
- Loss of consciousness, or if you faint.
- A fast or slow heart rate.
- Very low or very high blood pressure.
- Large amounts of blood in your stool, or you are vomiting blood.
- A seizure.
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