Duloxetine is an antidepressant medication. It affects chemicals in the brain that may become unbalanced and cause depression. It is used to treat major depressive disorder (MDD) and for the management of pain associated with diabetic peripheral neuropathy. Duloxetine may also be used for purposes other than those listed in this medication guide.
Take duloxetine exactly as directed by your doctor. If you do not understand these instructions, ask your pharmacist, nurse, or doctor to explain them to you. Take each dose with water. Duloxetine capsules should be swallowed whole and should not be chewed or crushed, nor should the contents be sprinkled on food or mixed with liquids. Duloxetine may be taken with or without food. Try to take duloxetine at the same time each day. Do not stop taking duloxetine without first talking to your doctor. It may take several weeks before you start feeling better. It is important to take duloxetine regularly to get the most benefit. Your doctor may want to perform tests or schedule appointments to monitor your treatment with duloxetine. Store duloxetine at room temperature away from moisture and heat.
If you experience any of the following serious side effects, stop taking duloxetine and contact your doctor immediately or seek emergency medical treatment: an allergic reaction (difficulty breathing; closing of the throat; swelling of the lips, tongue, or face; or hives); an irregular heartbeat or pulse; low blood pressure (dizziness, weakness); high blood pressure (severe headache, blurred vision); chills or fever; unusual bleeding or bruising; a rash or hives.
If you experience any of the following less serious side effects, continue taking duloxetine and talk to your doctor: headache, tremor, nervousness, or anxiety; difficulty concentrating; constipation; nausea, diarrhea, dry mouth, or changes in appetite or weight; weakness; increased sweating; sleepiness or insomnia; or decreased sex drive, impotence, or difficulty having an orgasm.
Use caution when driving, operating machinery, or performing other hazardous activities. Duloxetine may cause dizziness or drowsiness. If you experience dizziness or drowsiness, avoid these activities. Avoid alcohol during treatment with duloxetine. Together, alcohol and duloxetine can be damaging to the liver.
Do not take duloxetine if you have taken a monoamine oxidase inhibitor (MAOI) such as isocarboxazid (Marplan), phenelzine (Nardil), or tranylcypromine (Parnate) during the last 2 weeks. Wait at least 5 days after you stop taking duloxetine before taking a MAOI. Serious, and sometimes fatal, reactions have occurred when these medicines have been used together. Also, do not take duloxetine if you are taking thioridazine (Mellaril). Dangerous, even fatal irregular heartbeats may occur if these medicines are taken together. You must wait 5 weeks after stopping duloxetine before taking thioridazine (Mellaril).
Duloxetine hydrochloride is a selective serotonin and norepinephrine reuptake inhibitor (SSNRI) for oral administration. Its chemical designation is (+)-(S)-N-methyl-g-(1- naphthyloxy)-2-thiophenepropylamine hydrochloride. The empirical formula is C18H19NOS.HCl, which corresponds to a molecular weight of 333.88. Each capsule contains enteric-coated pellets of 22.4, 33.7, or 67.3 mg of duloxetine hydrochloride equivalent to 20, 30, or 60 mg of duloxetine, respectively. These enteric-coated pellets are designed to prevent degradation of the drug in the acidic environment of the stomach. Inactive ingredients include FD&C Blue No. 2, gelatin, hypromellose, hydroxypropyl methylcellulose acetate succinate, sodium lauryl sulfate, sucrose, sugar spheres, talc, titanium dioxide, and triethyl citrate. The 20 and 60 mg capsules also contain iron oxide yellow.
Duloxetine has the following structural formula: