Many medications can cause side effects. A side effect is an unwanted response to a medication when it is taken in normal doses. Side effects can be mild or severe, temporary or permanent.

The side effects listed below are not experienced by everyone who takes Intelence. If you are concerned about side effects, discuss the risks and benefits of Intelence with your doctor.

The following side effects have been reported by at least 1% of people taking Intelence. Many of these side effects can be managed, and some may go away on their own over time.

Contact your doctor if you experience these side effects and they are severe or bothersome. Your pharmacist may be able to advise you on managing side effects.

• abdominal pain
• anxiety
• Diarrhea
• fatigue
• gas
• headache
• heartburn
• changes in fat distribution (increased fat in the upper back and neck, breasts, and trunk; and loss of fat from the arms, legs, and face)
• nausea
• night sweats
• numbness
• tingling or pain in the hands or feet
• trouble sleeping
• vomiting

Although most of the side effects listed below don't happen very often, they could lead to serious problems if you do not seek medical attention.

Check with your doctor as soon as possible if any of the following side effects occur:

• muscle pain, tenderness or weakness
• signs of Anemia (low red blood cells; e.g., dizziness, pale skin, unusual tiredness or weakness, shortness of breath)
• signs of clotting problems (e.g., unusual nosebleeds, bruising, blood in urine, coughing blood, bleeding gums, cuts that don't stop bleeding)
• signs of infection (symptoms may include Fever or chills, severe diarrhea, shortness of breath, prolonged dizziness, headache, stiff neck, weight loss, or listlessness)
• skin rash
• symptoms of Diabetes (e.g., excessive thirst, urination, or eating; unexplained weight loss; poor wound healing; infections)
• symptoms of high blood pressure (e.g., headache, dizziness, blurred vision, nausea)
• symptoms of kidney problems (e.g., nausea, loss of appetite, weakness, passing little or no urine, breathlessness)
• symptoms of liver problems (e.g., abdominal pain, persistent vomiting, feeling unwell, fever, itching, yellowing of the skin and eyes, dark urine)

Stop taking the medication and seek immediate medical attention if any of the following occur:

• fever
• signs of a Heart Attack (e.g., chest pain or pressure, pain extending through shoulder and arm, nausea and vomiting, sweating)
• signs of a severe skin reaction such as blistering, peeling, a rash covering a large area of the body, a rash that spreads quickly, or a rash combined with fever or discomfort
• symptoms of a Anaphylaxis (severe allergic reaction) (e.g., Hives; shortness of breath; or swelling of the face, lips, or tongue)

Some people may experience side effects other than those listed. Check with your doctor if you notice any symptom that worries you while you are taking Intelence.

25 mg
Each white-to-off-white, oval, scored tablet debossed with "T125" on one side contains 25 mg of etravirine. Nonmedicinal ingredients: hypromellose, microcrystalline cellulose, colloidal anhydrous silica, croscarmellose sodium, magnesium stearate, and lactose monohydrate.

100 mg
Each white-to-off-white, oval tablet, debossed with "T125" on one side and "100" on the other side, contains 100 mg of etravirine. Nonmedicinal ingredients: colloidal silicon dioxide, croscarmellose sodium, hypromellose, lactose monohydrate, magnesium stearate, and microcrystalline cellulose.

200 mg
Each white-to-off-white, biconvex, oblong tablet debossed with "T200" on one side contains 200 mg of etravirine. Nonmedicinal ingredients: hypromellose, colloidal silicon dioxide, croscarmellose sodium, magnesium stearate, silicified microcrystalline cellulose, and microcrystalline cellulose.

Do not take Intelence if you are allergic to etravirine or any ingredients of the medication.

There may be an interaction between etravirine and any of the following:

• alpha blockers (e.g., Alfuzosin, Doxazosin, Tamsulosin)
• antiarrythmics (e.g., Amiodarone, Disopyramide, Mexiletine, Propafenone)
• anti-cancer medications (e.g., Cabazitaxel, Docetaxel, Doxorubicin, Etoposide, Ifosfamide, Irinotecan, Vincristine)
• anti-psychotics (e.g., Chlorpromazine, Clozapine, Haloperidol, Olanzapine, Quetiapine, Risperidone)
• Apixaban
• Aprepitant
• "azole" antifungals (e.g., itraconazole, ketoconazole, Voriconazole)
• barbiturates (e.g., Phenobarbital, secobarbital)
• benzodiazepines (e.g., Clonazepam, Diazepam, Lorazepam)
• Bosentan
• Buspirone
• Calcitriol
• calcium channel blockers (e.g., Amlodipine, Diltiazem, Nifedipine, Verapamil)
• cannabis
• Carvedilol
• Celecoxib
• chloroquine
• Cobicistat
• conivaptan
• Cyclosporine
• Cyproterone
• Dantrolene
• Dapsone
• Deferasirox
• Dexamethasone
• Digoxin
• Enzalutamide
• ergot alkaloids (e.g., Dihydroergotamine, ergonovine,  ergotamine, methylergonovine)
• estrogens (e.g., conjugated estrogen, Estradiol, ethinyl estradiol)
• fluticasone
• Guanfacine
• Hepatitis C antivirals (e.g., daclatasvir, dasabuvir, ledipasvir, paritaprevir, ombitasvir, simeprevir, sofosbuvir)
• HIV protease inhibitors (e.g., indinavir, atazanavir, lopinavir, nelfinavir, ritonavir)
• Losartan
• macrolide antibiotics (e.g., clarithromycin, erythromycin)
• maraviroc
• Mefloquine
• Methadone
• mifepristone
• Mirtazapine
• Mitotane
• Modafinil
• Montelukast
• narcotic pain relievers (e.g., Fentanyl, Hydrocodone, Oxycodone)
• nefazodone
• nitrates (e.g., isosorbide dinitrate,  isosorbide mononitrate)
• Ondansetron
• Orlistat
• other HIV non-nucleoside reverse transcriptase inhibitors (NNRTIs; e.g., delavirdine, efavirenz, nevirapine)
• phosphodiesterase 5 inhibitors (e.g., Sildenafil, Tadalafil, Vardenafil)
• praziquantel
• Primaquine
• progestins (e.g., Dienogest, Levonorgestrel, medroxyprogesterone, Norethindrone)
• proton pump inhibitors (e.g., Lansoprazole, Omeprazole
• quinidine
• quinine
• Rivaroxaban
• Repaglinide
• rifabutin (when given along with a protease inhibitor such as darunavir, ritonavir, saquinavir)
• rifampin
• rilpivirine
• rivaroxaban
• Romidepsin
• St. John's wort
• seizure medications (e.g., Carbamazepine, Gabapentin, Levetiracetam, Phenytoin, Topiramate)
• selective serotonin reuptake inhibitors (SSRIS; e.g., Citalopram, Fluoxetine, Paroxetine, Sertraline)
• siltuximab
• Sirolimus
• Solifenacin
• "statin" anti-cholesterol medications (e.g., Atorvastatin, Lovastatin, Simvastatin)
• sulfonamide antibiotics (‘sulfas'; e.g., sulfisoxazole, sulfamethoxazole)
• sulfonylureas (e.g., Gliclazide, Glyburide, Tolbutamide)
• Tacrolimus
• Tamoxifen
• Tetracycline
• Theophylline
• Ticagrelor
• Ticlopidine
• Tocilizumab
• Tolterodine
• Tolvaptan
• Tramadol
• Trazodone
• tricyclic antidepressants (e.g., Amitriptyline, Clomipramine, Desipramine, Trimipramine)
• Trimethoprim
• tyrosine kinase inhibitors (e.g., Bosutinib, Dabrafenib, imatinib, Lapatinib)
• Venlafaxine
• Warfarin
• Zafirlukast
• Zolpidem
• Zopiclone

If you are taking any of these medications, speak with your doctor or pharmacist. Depending on your specific circumstances, your doctor may want you to:

• stop taking one of the medications,
• change one of the medications to another,
• change how you are taking one or both of the medications, or
• leave everything as is.

An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.

Medications other than those listed above may interact with Intelence. Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications you are taking. Also tell them about any supplements you take. Since caffeine, alcohol, the Nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them.

Before you begin using a medication, be sure to inform your doctor of any medical conditions or Allergies you may have, any medications you are taking, whether you are pregnant or breastfeeding, and any other significant facts about your health. These factors may affect how you should use Intelence.

Blood tests: Etravirine can cause changes in your blood test results, such as red blood cell count, platelet count, cholesterol level, and sugar level. Your doctor will explain these to you and monitor your blood levels.

Fat redistribution: Over time, Intelence may change how fat is distributed in your body and may change your body shape. You may notice increased fat in the upper back, neck, and breast, as well as around the back, chest, and stomach area. You may also notice loss of fat from the legs, arms, and face. The long-term effects of this are not known.

Immune reconstitution syndrome: Intelence may cause immune reconstitution syndrome, where signs and symptoms of inflammation from previous infections appear. These symptoms occur soon after starting anti-HIV medication and can vary. They are thought to occur as a result of the immune system improving and being able to fight infections that have been present without symptoms, such as pneumonia, herpes, or Tuberculosis. Report any new symptoms to your doctor immediately.

Lactose intolerance: Intelence contains lactose. If you have galactose intolerance (galactosemia, glucose-galactose malabsorption, or Lapp lactase deficiency) you should not take Intelence. Talk to your doctor about other alternatives.

Liver function: Etravirine may reduce liver function and can cause liver failure. If you experience symptoms of liver problems such as fatigue, feeling unwell, loss of appetite, nausea, yellowing of the skin or whites of the eyes, dark urine, pale stools, abdominal pain or swelling, and itchy skin, contact your doctor immediately.

If you have severe liver problems or decreased liver function, discuss with your doctor how Intelence may affect your medical condition, how your medical condition may affect the dosing and effectiveness of Intelence, and whether any special monitoring is needed.

Pancreatitis: Intelence may rarely cause inflammation of the pancreas (pancreatitis). If you have a history of or are at risk for developing pancreatitis, you should be closely monitored by your doctor while taking Intelence. If you develop signs of pancreatitis (e.g., upper left abdominal pain, back pain, nausea, fever, chills, rapid heartbeat, swollen abdomen), contact your doctor.

Skin rashes: Intelence can cause skin rash, which is usually mild to moderate in severity. However, etravirine can also cause severe skin reactions. If you develop a skin rash while taking Intelence, contact your doctor immediately. If the rash is severe and you also have a fever, muscle or joint aches, blisters, or facial swelling, stop taking the medication and get immediate medical attention.

Pregnancy: Intelence should not be used during pregnancy unless the benefits outweigh the risks. If you become pregnant while taking Intelence, contact your doctor immediately.

Breast-feeding: It is not known if etravirine passes into breast milk. Women who have HIV are cautioned against breast-feeding because of the risk of passing HIV to a baby who does not have the infection.

Children: The safety and effectiveness of using Intelence have not been established for children less than 6 years of age.

Seniors: Seniors are more likely to have reduced kidney, liver and heart function or other diseases, which may cause an increase in side effects. Lower than the usual adult doses may be needed.