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 Reyataz. If you are concerned about side effects, discuss the risks and benefits of Reyataz with your doctor.

The following side effects have been reported by at least 1% of people taking Reyataz. 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
• headache
• nausea or vomiting (infrequent)
• rash

Although most of these 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:

• nausea or vomiting (frequent)
• rapid heartbeat
• signs of gallstones (e.g., nausea, vomiting, severe abdominal pain)
• signs of liver problems (e.g., nausea, vomiting, Diarrhea, loss of appetite, weight loss, yellowing of the skin or whites of the eyes, dark urine, pale stools)
• symptoms of an autoimmune disorder (e.g., Fever, unusual joint or muscle pain, rash, fatigue)
• symptoms of high blood sugar (e.g., frequent urination, increased thirst, excessive eating, unexplained weight loss, poor wound healing, infections, fruity breath odour)
• symptoms of irregular heartbeat (e.g., chest pain, dizziness, rapid, pounding heartbeat, shortness of breath)
• weight loss

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

• signs of an allergic reaction (shortness of breath or difficulty breathing; Hives; swelling of the eyes, mouth, lips, or throat)
• signs of Kidney Stones (pain in your side, blood in urine, pain when urinating)
• symptoms of a condition called lactic acidosis (unusual weakness or tiredness, unusual muscle pain, stomach pain with nausea and vomiting, feeling cold especially in arms and legs, dizziness or lightheadedness, and fast or irregular heartbeat)

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 Reyataz.

150 mg
Each blue opaque cap and powder-blue opaque body, hard gelatin capsule, printed in white with "BMS", "150 mg", and in blue "3624" contains atazanavir sulfate equivalent to 150 mg of atazanavir. Nonmedicinal ingredients: crospovidone, lactose monohydrate, and magnesium stearate; capsule shell: FD&C Blue No. 2, gelatin, and titanium dioxide.

200 mg
Each blue opaque cap and body, hard gelatin capsule, printed in white with "BMS", "200 mg", and "3631" contains atazanavir sulfate equivalent to 200 mg of atazanavir. Nonmedicinal ingredients: crospovidone, lactose monohydrate, and magnesium stearate; capsule shell: FD&C Blue No. 2, gelatin, and titanium dioxide.

300 mg
Each red opaque cap and blue opaque body, hard gelatin capsule, printed in white with "BMS", "300 mg", and "3622" contains atazanavir sulfate equivalent to 300 mg of atazanavir. Nonmedicinal ingredients: crospovidone, lactose monohydrate, and magnesium stearate; capsule shell: black iron oxide, FD&C Blue No. 2, gelatin, red iron oxide, titanium dioxide, and yellow iron oxide.

Do not take atazanavir if you:

• are allergic to atazanavir or any ingredients of the medication
• are taking any of the following medications:
• Alfuzosin
• Apixaban (if also taking ritonavir)
• ergot-type medications (i.e., Dihydroergotamine, ergonovine, ergotamine, or methylergonovine)
• Hepatitis C direct acting antivirals (e.g., elbasvir, grazoprevir, glecaprevir, pibrentasvir)
• indinavir
• Irinotecan
• Lovastatin
• Lomitapide
• Lurasidone (if also taking ritonavir)
• nevirapine
• Pimozide
• Quetiapine
• quinidine
• rifampin
• Rivaroxaban (if also taking ritonavir)
• Sildenafil (when used for pulmonary arterial hypertension)
• Simvastatin
• St. John's wort
• Triazolam

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

• Alitretinoin
• alpha-blockers (e.g., alfuzosin, Doxazosin, Silodosin, Tamsulosin)
• Amiodarone
• antacids (e.g., aluminum hydroxide, calcium carbonate, magnesium hydroxide)
• anticancer medications (e.g., Cabazitaxel, Docetaxel, Doxorubicin, Etoposide, Ifosfamide, irinotecan, Vincristine)
• antipsychotics (e.g., Clozapine, Haloperidol, lurasidone, Olanzapine, pimozide, quetiapine, Risperidone)
• Apalutamide
• apixaban
• Aprepitant
• "azole" antifungals (e.g., fluconazole, itraconazole, ketoconazole, Voriconazole)
• benzodiazepines (e.g., Chlordiazepoxide, Clonazepam, Diazepam, Lorazepam, midazolam, triazolam)
• birth control pills (estrogen and progestin)
• Bosentan
• Bromocriptine
• Buprenorphine
• Buspirone
• calcifediol
• Calcitriol
• calcium channel blockers (e.g., diltiazem, Felodipine, nicardipine, Nifedipine, verapamil)
• cannabis
• Cobicistat
• Colchicine
• conivaptan
• corticosteroids (e.g., Dexamethasone, fluticasone, Hydrocortisone, Prednisone)
• Cyclosporine
• dabigatran
• Dapsone
• Darifenacin
• Deferasirox
• Degarelix
• diabetes medications (e.g., Canagliflozin, Glyburide, insulin, Linagliptin, Metformin, Repaglinide, Rosiglitazone, Sitagliptin)
• Disopyramide
• Domperidone
• Dronedarone
• Dutasteride
• Elagolix
• Eliglustat
• Eluxadoline
• enfuvirtide
• Enzalutamide
• Eplerenone
• ergotamine or ergot-type medications (e.g., dihydroergotamine, ergonovine, or methylergonovine)
• estrogens (e.g., conjugated estrogen, Estradiol, ethinyl estradiol)
• Everolimus
• Flibanserin
• Galantamine
• grapefruit juice
• Guanfacine
• H2 antagonists (e.g., Famotidine, Ranitidine)
• hepatitis C antivirals (e.g., glecaprevir and pibrentasvir, grazoprevir, ledipasvir, sofosbuvir)
• HIV integrase inhibitors (e.g., bictegravir, dolutegravir, elvitegravir, raltegravir)
• HIV non-nucleoside reverse transcriptase inhibitors (NNRTIs; e.g., efavirenz, etravirine, nevirapine)
• other HIV protease inhibitors (e.g., indinavir, ritonavir, saquinavir)
• HIV nucleoside reverse transcriptase inhibitors (NRTIs; e.g., abacavir, didanosine, lamivudine, tenofovir, zidovudine)
• Ivabradine
• Ivacaftor
• lidocaine
• lomitapide
• lumacaftor and ivacaftor
• Macitentan
• macrolide antibiotics (e.g., clarithromycin, erythromycin)
• maraviroc
• Mefloquine
• Methadone
• mifepristone
• Minocycline
• Minoxidil
• Mirtazapine
• Modafinil
• Naloxegol
• narcotics (e.g., Codeine, Fentanyl, Morphine, Oxycodone)
• nitrates (e.g., isosorbide dinitrate, isosorbide mononitrate)
• Orlistat
• Oxybutynin
• phosphodiesterase (PDE 5) inhibitors (e.g., sildenafil, Tadalafil, Vardenafil)
• Pimecrolimus
• praziquantel
• progestins (e.g., Dienogest, Levonorgestrel, medroxyprogesterone, Norethindrone)
• Propafenone
• protein kinase inhibitors (e.g., Bosutinib, imatinib, Nilotinib)
• proton pump inhibitors (e.g., Lansoprazole, Omeprazole)
• quinidine
• quinine
• rifabutin
• rifampin
• rilpivirine
• Riociguat
• rivaroxaban
• Romidepsin
• rupatadine
• St. John's wort
• salmeterol
• Sarilumab
• seizure medications (e.g., Carbamazepine, Clobazam, Levetiracetam, Phenobarbital, Phenytoin, primidone, Topiramate, Valproic acid, zonisamide)
• siltuximab
• Sirolimus
• Solifenacin
• "statin" anti-cholesterol medications (e.g., Atorvastatin, lovastatin, simvastatin)
• Tacrolimus
• Tamoxifen
• Ticagrelor
• Tocilizumab
• Tolterodine
• Tolvaptan
• Tramadol
• Trazodone
• tricyclic antidepressants (e.g., Amitriptyline, Desipramine, Imipramine, Nortriptyline)
• "triptan" migraine medications (e.g., Almotriptan, Eletriptan)
• Ulipristal
• Vilazodone
• Warfarin
• 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 Reyataz. 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 breast-feeding, and any other significant facts about your health. These factors may affect how you should use Reyataz.

Diabetes: Some people taking protease inhibitor medications such as atazanavir have developed diabetes during treatment, and some people who already had diabetes noticed that their diabetes became worse during treatment. If you have diabetes, discuss with your doctor how Reyataz may affect your medical condition, how your medical condition may affect the dosing and effectiveness of Reyataz, and whether any special monitoring is needed.

Gallstones: Atazanavir can cause gallstones, concentrations of the bile that is produced by the liver. If you experience symptoms of gallstones, such as persistent severe pain on the right side of your abdomen, nausea and vomiting, or pain between the shoulder blades or under the right shoulder, contact your doctor as soon as possible.

Heart effects: Atazanavir can affect heart rhythm (heartbeat) for some people. If you have problems with the electrical conduction system of your heart (e.g., first-, second-, and third-degree AV block) or are taking medications that affect the electrical conduction system of the heart (e.g., Diltiazem, Verapamil), discuss with your doctor how Reyataz may affect your medical condition, how your medical condition may affect the dosing and effectiveness of Reyataz, and whether any special monitoring is needed.

Hemophilia: People with hemophilia A or B may be at an increased risk of bleeding while taking atazanavir. If you have a bleeding condition, discuss with your doctor how Reyataz may affect your medical condition, how your medical condition may affect the dosing and effectiveness of Reyataz, and whether any special monitoring is needed.

Immune reconstitution inflammatory syndrome: When you start taking HIV medications such as atazanavir, your immune system may get stronger and start to fight other infections that have been hidden in your body (e.g., pneumonia, herpes, or Tuberculosis). Contact your doctor if you develop any new symptoms after starting HIV medications such as atazanavir.

Kidney function: Chronic Kidney Disease has been reported with the use of atazanavir. If you have a history of kidney disease, discuss with your doctor how Reyataz may affect your medical condition, how your medical condition may affect the dosing and effectiveness of Reyataz, and whether any special monitoring is needed.

Kidney stones: Some people taking atazanavir have developed kidney stones. If you develop signs or symptoms of kidney stones (e.g., pain in your side, blood in your urine, or pain when you urinate), contact your doctor immediately.

Lactic acidosis: People taking atazanavir in combination with some other HIV medications (e.g., abacavir, didanosine, lamivudine, and zidovudine) may be at risk of a serious condition called lactic acidosis. Lactic acidosis is a buildup of lactic acid in the blood. If you notice any of the symptoms of lactic acidosis, such as difficulty breathing, abdominal pain, muscle weakness, nausea, and vomiting, stop taking Reyataz and contact your doctor immediately.

Lactose: Reyataz contains lactose. If you have hereditary problems of galactose intolerance, lactase deficiency, or glucose-galactose malabsorption, talk to your doctor about whether Reyataz is appropriate for you.

Liver function: Liver disease or reduced liver function may cause Reyataz to build up in the body, causing side effects. Reyataz can also cause liver failure and reduced liver function. People with hepatitis B or C, or liver disease, may experience worsening of their liver disease symptoms while taking Reyataz. Your doctor will monitor your liver function while you are taking atazanavir. Report any signs of liver problems (e.g., nausea, vomiting, diarrhea, loss of appetite, weight loss, yellowing of the skin or whites of the eyes, dark urine, pale stools) to your doctor immediately. People with severe liver disease should not take Reyataz.

Other medications: Atazanavir may interact with a number of medications, which may mean a change in how you take Reyataz (see "What medications can interact with Reyataz?"). Tell your doctor about all the medications that you are taking. Certain medications should not be taken with atazanavir at all (see "Who should NOT take Reyataz?").

Atazanavir should never be used alone; it should always be used in combination with other HIV medications.

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

Breast-feeding: Reyataz passes into breast milk. If you are breast-feeding and are taking atazanavir, it may affect your baby. Breast-feeding is not recommended for HIV-positive women since the virus can be transmitted through breast milk.

Children and adolescents: The safety and effectiveness of using Reyataz have not been established for children between 3 months and 6 years of age. Do not give Reyataz to children younger than 3 months as it can cause a form of brain damage known as kernicterus.