An Overview of Side Effects of Furosemide 

As with any medicine,  side effects can occur with furosemide (Lasix®). However, not everyone who takes the  medication will have problems. In fact, most people tolerate it well. If side effects do occur, in most cases, they are minor and either require no treatment or can be easily treated by you or your healthcare provider. 

Furosemide Side Effects to Report 

Some side effects with this drug are potentially serious  and should be reported immediately to  your healthcare provider. 

These include but  are not limited to:

• Dizziness, lightheadedness, or fainting spells 
• Signs of dehydration or low electrolytes, such as: 

1. Dry mouth
2. Thirst
3. Weakness  
4. Lethargy
5. Drowsiness
6. Restlessness
7. Muscle pain or muscle cramps 
8. Low blood pressure (hypotension) 
9. Decreased urination 
10. A rapid heart rate (tachycardia) or irregular heart rhythm (arrhythmia) 
11. Nausea or vomiting 

• Yellowing of the skin or the whites of the eyes (jaundice) 
• Ringing in the ears (tinnitus) or hearing problems 
• High blood sugar (hyperglycemia)
• Signs of an allergic reaction, including: 

1. An unexplained  rash
2. Hives  
3. Itching  
4. Unexplained swelling 
5. Wheezing  
6. Difficulty  breathing or swallowing.

• Constipation  or diarrhea 
• Vision changes 
• Headaches  
• Vertigo (a spinning sensation) 
• Anemia  
• Fever  
• Sensitivity to the sun.