Doxycycline

Doxycycline is a common antibiotic often used for the treatment of various infections, such as bacterial infections, anthrax, malaria, and acne. The medication is part of a class of drugs called tetracyclines, and works by decreasing bacteria's ability to make protein (which it needs to live). Doxycycline is available in several forms, and is usually taken once or twice a day.

What Is Doxycycline?

Doxycycline is a prescription antibiotic that is licensed to treat a number of common bacterial infections.
 

What Is It Used For?

Common uses for the drug include the following:
 
  • Treatment of bacterial infections, such as:
 
 
  • An alternative for malaria prevention
 
 

 

 

  • Treatment of periodontitis (gum disease). 

 

Doxycycline has not been approved for use in children under the age of eight.
 
(Click Doxycycline Uses for more information on each specific use.)
 

How Does It Work?

Doxycycline is part of a class of drugs called tetracyclines. It decreases bacteria's ability to make protein, which bacteria need to live. This activity does not directly kill the bacteria, but it does inhibit their growth and multiplication, which gives the immune system a chance to fight the infection. For treating gum disease, doxycycline actually works to inhibit an enzyme in the saliva known as collagenase.
 

When and How Do I Take It?

Considerations for people taking this drug include the following:
 
  • The medication comes as a capsule, tablet, syrup, oral suspension, gel, or injection. It is usually taken once or twice a day, depending on your healthcare provider's instructions and the particular product.
     
  • It works best when taken without food. However, some products can be taken with food if stomach upset occurs. Make sure to refer to the instructions for your specific product.
     
  • It is important to take doxycycline with plenty of water (or other fluids) while in an upright position, in order to prevent the medication from irritating the throat.
     
  • Doxycycline should be taken at the same time(s) each day to maintain an even level in your system.
     
  • For the drug to work properly, you have to take it as prescribed. Make sure that you complete your entire prescription of doxycycline, even if you start feeling better. This will ensure that the infection is completely treated.
      

Dietary Instructions With Doxycycline

There is conflicting information available about the possibility of an interaction with milk and doxycycline. While it is clear that doxycycline is less likely to interact with milk than other tetracyclines, researchers have not reached a definitive conclusion about whether or not milk might reduce the effectiveness of doxycycline. Most sources state that it is probably not a problem to combine doxycycline with milk.
 

Dosing Information for Doxycycline

The dosage that your healthcare provider recommends will vary, depending on a number of factors, including:
 
  • The particular doxycycline product
  • The condition being treated
  • Other medical conditions you may have
  • Other medications you are currently taking.
      
As is always the case, do not adjust your dose unless your healthcare provider specifically instructs you to do so.
 
(Click Doxycycline Dosage for more information.)
 

Side Effects of Doxycycline

As with any medicine, side effects are possible. However, not everyone who takes the drug will experience side effects. If side effects do occur, in most cases, they are minor, meaning that they require no treatment or are easily treated by your healthcare provider.
 
Common side effects of this drug include, but are not limited to:
 
  • Nausea
  • Diarrhea
  • Vomiting
  • Skin reaction to sunlight (photosensitivity)
  • Upset stomach (dyspepsia)
  • Unexplained rash
  • Loss of appetite
  • Yeast infection.
     
Potentially serious side effects can also occur with doxycycline, but these are less common.
 
(Click Doxycycline Side Effects to learn more.)
 

Drug Interactions With Doxycycline

Doxycycline may interact with a number of medicines (see Doxycycline Drug Interactions).
 

Doxycycline: What Should I Tell My Healthcare Provider?

You should talk to your healthcare provider prior to taking this drug if you:
 
  • Liver disease or liver failure
  • Kidney disease, such as kidney failure (renal failure)
  • Frequent yeast infections
  • Any other allergies, including allergies to food, dyes, or preservatives.
     
Also, let your healthcare provider know if you are:
 
Tell your healthcare provider about all medicines you are taking, including prescription and non-prescription medicines, vitamins, and herbal supplements.
 
(Click Doxycycline Precautions and Warnings to learn more, including information on who should not take the drug.)
 

What If I Take an Overdose of Doxycycline?

People who take too much of this medication may have overdose symptoms that could include, but are not limited to:
 
If you happen to overdose on doxycycline, seek immediate medical attention (see Doxycycline Overdose).
 

How Should It Be Stored?

Doxycycline capsules and tablets should be stored at room temperature and kept protected from light.
 
Keep doxycycline and all medications out of the reach of children.
 

What Should I Do If I Miss a Dose?

If you do not take your dosage as scheduled, take the missed dose as soon as possible. However, if it is almost time for the next dose, simply skip the missed dose and continue with your regular schedule. Do not take a double dose.
 

Strengths of Doxycycline

Doxycycline comes in a number of strengths. These include:
 
  • Doxycycline 20 mg tablets (Alodox Periostat)
  • Doxycycline 50 mg, 75, 100, and 150 mg tablets and capsules (Doryx®, Monodox®, NutriDox, Vibramycin®, Vibra-Tabs®)
  • Doxycycline 40 mg delayed-release capsules (Oracea®)
  • Doxycycline 50 mg per 5 mL syrup (Vibramycin®)
  • Doxycycline 25 mg per 5 mL powder for oral suspension (Vibramycin®)
  • Doxycycline 10 percent gel (Atridox®)
  • Doxycycline 100 and 200 mg vials for injection.
      

Who Makes It?

Doxycycline is the generic name for an antibiotic medication manufactured by a number of companies, including:
 
  • Pfizer, Inc
  • Sandoz
  • Mutual Pharmaceutical Co., Inc.
  • Mylan Pharmaceuticals
  • Watson Laboratories
  • APP Pharmaceuticals
  • CollaGenex Pharmaceuticals, Inc.
  • Vintage Pharmaceutical, Inc. 
 

Generic Doxycycline

Doxycycline is a generic medication, but it is also available under a number of brand names. These brands include:
 
  • Adoxa®
  • Alodox®
  • Atridox®
  • Doryx®
  • Monodox®
  • NutriDox
  • Oracea
  • Periostat®
  • Vibra-Tabs®
  • Vibramycin®
Written by/reviewed by: Kristi Monson, PharmD; Arthur Schoenstadt, MD
Last reviewed by: Kristi Monson, PharmD;
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