Medical use
- Treatment of Lyme disease
- Treatment of chronic prostatitis
- Treatment of sinusitis
- Treatment of pelvic inflammatory disease
- Treatment of rickettsial infections

Antibacterial
- Effective against Moraxella catarrhalis
- Effective against Brucella melitensis
- Effective against Chlamydia pneumoniae
- Effective against Mycoplasma pneumoniae
- Some strains of Pseudomonas aeruginosa have developed resistance

Antimalarial
- Active against erythrocytic stages of Plasmodium falciparum
- Not active against gametocytes
- Used in the treatment of malaria
- Can be used as prophylaxis against malaria
- Targeting a plastid organelle, the apicoplast

Side effects
- Diarrhea
- Nausea
- Vomiting
- Abdominal pain
- Increased risk of sunburn

Commercial use and availability
- Patented in 1957
- Came into commercial use in 1967
- Included in the World Health Organization's List of Essential Medicines
- Available as a generic medicine
- 79th most commonly prescribed medication in the United States in 2020 with over 9 million prescriptions

Doxycycline (Wikipedia)

Doxycycline is a broad-spectrum antibiotic of the tetracycline class used in the treatment of infections caused by bacteria and certain parasites. It is used to treat bacterial pneumonia, acne, chlamydia infections, Lyme disease, cholera, typhus, and syphilis. It is also used to prevent malaria. Doxycycline may be taken by mouth or by injection into a vein.

Doxycycline

Clinical data
Pronunciation	/ˌdɒksɪˈsaɪkliːn/ DOKS-iss-EYE-kleen
Trade names	Doxy, Doryx, Vibramycin, others
AHFS/Drugs.com	Monograph
MedlinePlus	a682063
License data	US DailyMed: Doxycycline
Pregnancy category	AU: D
Routes of administration	By mouth, intravenous
ATC code	J01AA02 (WHO) A01AB22 (WHO)
Legal status
Legal status	AU: S4 (Prescription only) UK: POM (Prescription only) US: ℞-only
Pharmacokinetic data
Bioavailability	~100%
Protein binding	80–90%
Metabolism	Negligible
Elimination half-life	10–22 hours
Excretion	Mainly feces, 40% urine
Identifiers
IUPAC name (4S,4aR,5S,5aR,6R,12aS)-4-(Dimethylamino)-3,5,10,12,12a-pentahydroxy-6-methyl-1,11-dioxo-1,4,4a,5,5a,6,11,12a-octahydrotetracene-2-carboxamide
CAS Number	564-25-0 Y
PubChem CID	Doxycycline
DrugBank	DB00254 Y
ChemSpider	10482106 Y
UNII	334895S862
KEGG	D07876 N
ChEBI	CHEBI:60648 Y
ChEMBL	ChEMBL1433 N
CompTox Dashboard (EPA)	DTXSID0037653
ECHA InfoCard	100.008.429
Chemical and physical data
Formula	C22H24N2O8
Molar mass	444.440 g·mol−1
3D model (JSmol)	Interactive image
SMILES CN(C)[C@@H]3C(\O)=C(\C(N)=O)C(=O)[C@@]4(O)C(/O)=C2/C(=O)c1c(cccc1O)[C@H](C)[C@H]2[C@H](O)[C@@H]34
InChI InChI=1S/C22H24N2O8.H2O/c1-7-8-5-4-6-9(25)11(8)16(26)12-10(7)17(27)14-15(24(2)3)18(28)13(21(23)31)20(30)22(14,32)19(12)29;/h4-7,10,14-15,17,25,27-29,32H,1-3H3,(H2,23,31);1H2/t7-,10+,14+,15-,17-,22-;/m0./s1 Y Key:XQTWDDCIUJNLTR-CVHRZJFOSA-N Y
NY (what is this?)  (verify)

Common side effects include diarrhea, nausea, vomiting, abdominal pain, and an increased risk of sunburn. Use during pregnancy is not recommended. Like other agents of the tetracycline class, it either slows or kills bacteria by inhibiting protein production. It kills malaria by targeting a plastid organelle, the apicoplast.

Doxycycline was patented in 1957 and came into commercial use in 1967. It is on the World Health Organization's List of Essential Medicines. Doxycycline is available as a generic medicine. In 2020, it was the 79th most commonly prescribed medication in the United States, with more than 9 million prescriptions.